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The linear power amplifier (LPA) suffers from low power supply utilization in the DC power supply mode, leading to reduced output efficiency. This paper constructs an efficient power supply mode based on closed‐loop dynamic power supply system (CLDPSs). The CLDPSs can generate a pair of bipolar dynamic power supplies based on a predetermined signal to provide power to LPA, which can maintain a small voltage drop between the power supply and the output of LPA, thereby improving the power supply utilization of LPA. In addition, the study also focuses on the conflicting relationship between the output ripple and the dynamic performance of the CLDPSs, for which a new parametric design of the LC filter circuit is proposed, aiming to achieve a balance between these two aspects. Finally, a voice coil motor driving platform is constructed for experimental testing. The results demonstrate that the output ripple and dynamic performance of the CLDPSs can be balanced. In comparison to the DC power supply mode, the CLDPSs power supply mode can enhance the efficiency of LPA by 2 times while the driving accuracy of voice coil motor is basically unchanged. [ABSTRACT FROM AUTHOR]

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Stimulated by the challenging and accurate article by Stefano Fissi (2024), who draws on the latest works by Anil Seth and Mark Solms to address much-discussed topics in the current phase of the debate on the possibility of a mutual validation between cognitive neuroscience and psychoanalysis, some fundamental themes are discussed, indicating epistemological problems and understandable argumentative weaknesses. [ABSTRACT FROM AUTHOR]

This paper explores the concept of drives as basic motivational neurobiological structures determining the organization of psychic life. I express my agreement with Mark Solms' radical reformulation of the general principles organizing human behaviour at the neurobiological and psychodynamic levels, his combination of Friston's computational information theory and Panksepp's affect systems. I agree with him that the affect systems described by Panksepp constitute the primary drives and that the conflicts between affect systems are the origin of unconscious intrapsychic conflict. I disagree with Solms in my proposition that, while the original unconscious conflicts indeed reflect conflicts between antagonistic affects, I believe that the integration of affect systems into internalized object relations determines a significant motivational shift: now unconscious conflicts are between complex organization of idealized and persecutory object relations at oedipal and preoedipal levels, and no longer between affect systems themselves. At the various developmental levels, the integrated fusion of affective components of these conflicts in effect evolves into libido and aggression as supraordinate motivational systems, but they no longer can be considered biological drives. [ABSTRACT FROM AUTHOR]

Understanding the drivers and ecological effects of river water temperature (Tw) change remains a complex and challenging task in the field of ecohydrology. We developed the extreme‐point symmetric mode decomposition to quantitatively identify the trend, period and mutation of water temperature (Tw). The sparrow search algorithm‐long short‐term memory model was constructed to reconstruct the historical Tw to quantitatively identify the effects of human activities (HA) and climate change (CC) at different time scales. The random forest method was used to analyse the contribution rates of different meteorological factors and to clarify the main factors. Our results demonstrate that the Tw had a cooling trend in the 1980s, and the other decades have a warming trend, and the annual Tw distribution shows an obvious 'unimodal' distribution. The interannual Tw has a short period of 2–3a, 6–12a and a long period of 10–15a. At the interannual scale, as the distance from estuaries decreases, the influence of HA gradually diminishes, and only the great Tw is governed by CC. Contributions from HA and CC to Tw vary at the seasonal and monthly scales due to geographical differences. In Cuntan, the contribution of HA to Tw is greater than that of climatic factors. The contribution rates of climatic and HA in the three regions of Yichang, Hankou and Datong also exhibit their respective characteristics and fluctuation patterns. The maximum temperature is the most important factor affecting the change of Tw. Abnormal Tw changes result in delayed spawning and characteristic reproduction Tw attainment dates for the Four Major Chinese Carps and Acipenser sinensis. [ABSTRACT FROM AUTHOR]

Abstract The linear power amplifier (LPA) suffers from low power supply utilization in the DC power supply mode, leading to reduced output efficiency. This paper constructs an efficient power supply mode based on closed‐loop dynamic power supply system (CLDPSs). The CLDPSs can generate a pair of bipolar dynamic power supplies based on a predetermined signal to provide power to LPA, which can maintain a small voltage drop between the power supply and the output of LPA, thereby improving the power supply utilization of LPA. In addition, the study also focuses on the conflicting relationship between the output ripple and the dynamic performance of the CLDPSs, for which a new parametric design of the LC filter circuit is proposed, aiming to achieve a balance between these two aspects. Finally, a voice coil motor driving platform is constructed for experimental testing. The results demonstrate that the output ripple and dynamic performance of the CLDPSs can be balanced. In comparison to the DC power supply mode, the CLDPSs power supply mode can enhance the efficiency of LPA by 2 times while the driving accuracy of voice coil motor is basically unchanged.

Nietzsche offers us an account of how different drives interact with one another; it is rich but also appears to risk the homunculus fallacy. Competing attempts to deflect this charge on his behalf share an implicit consensus about the 'epistemic ends' of the account: they assume Nietzsche is trying to provide true explanations of psychological phenomena. I argue against this consensus. I claim that Nietzsche's characterisations of drive interaction are to be taken as fictive and are not intended to have explanatory value. They nevertheless facilitate genuine epistemic achievement. Drawing on Catherine Elgin's account of the epistemic role of idealised models in science, I argue that Nietzsche's account of drive interaction is a 'model of the mind' that, despite relying on falsehoods, can exemplify features of our psychology that aid us in making novel predictions. We then see that Nietzsche neatly sidesteps the homunculus fallacy; we can further understand more fully what Nietzsche hopes his drive psychology will teach us. We can now resolve, for example, outstanding interpretative puzzles about the relationship between psychic integration and Nietzsche's distinctive notion of spiritual health. [ABSTRACT FROM AUTHOR]

This study examined nontraditional students using linguistic inquiry and word count (LIWC) of their reflective writing assignments. Participants included 364 adult students enrolled in a degree completion program. Data comprised a multiweek reflective writing assignment and demographic data, linguistically and statistically analyzed. The study found that nontraditional students have low clout, a high drive for achievement, and a high motive of allure. In addition, students participating in credit for prior learning (CPL), also referred to as prior learning assessment (PLA), have statistically higher analytical thinking, drive for affiliation, and reward as motive. These results offer implications for prospective and nontraditional students, for academic advisors and instructors, and for higher education institutions and CPL programs. [ABSTRACT FROM AUTHOR]

The human‐environmental system in drylands is centered on oases. Despite its extent and socio‐ecological importance, understanding the dynamic changes of global oases and their human and environmental driving forces is imperative for sustainable development in drylands under global warming. Nevertheless, the dynamic changes of global oases and how they respond to the evolving environment are not well established. In this study, three criteria were summarized (i.e., existing in dryland climates, surrounded or partially surrounded by desert terrain, having a reliable source of freshwater and forming landscape units with higher vegetation coverage/productivity). A global oasis distribution map from 1995 to 2020 was generated using European Space Agency Climate Change Initiative Land Cover and GIMMS‐3G+ data (overall accuracy within a 95% confidence interval is 0.85 ± 0.01) based on overlay analysis and visual interpretation. In addition, we used geographic and temporal weighted regression methods to evaluate the potential macro‐level elements affecting both global and local oasis growth. The result showed that the global oases area in 2020 occupied an area of 191.91 Mha, and most oases existed in Asia (77.3%). The global oases area has significantly increased from 1995 to 2020 (+8.65 Mha). However, about 13.43 Mha of the global oases are desertified, indicating a high risk of desertification. Water resources, contributing 51.36% to the total driver's contribution, are key to the global oasis expansion. In the context of climate (climate variability and climate change), this research highlights the need for improved holistic water resource management for long‐term global oasis growth, particularly in developing countries where the oases' development is threatened by water scarcity and desertification. Plain Language Summary: In recent decades, global oases have exhibited an expanding trend. Under the backdrop of climate (climate variability and climate change), water resources profoundly influence this trend. We comprehensively assessed the distribution, dynamic changes, and factors driving the expansion of global oases. The research findings indicate that from 1995 to 2020, the global oasis area significantly increased by 8.65 Mha. However, approximately 13.43 Mha of global oases degraded into deserts, highlighting the extremely high risk of desertification. The abundance of water resources, accounting for 51.36% of the overall effect, emerges as the key determinant in global oasis growth. These findings emphasize the need for improved global comprehensive water resource management, particularly in developing countries' oasis regions, to address water scarcity and achieve the sustainable development of the oasis. Key Points: Global oases changed significantly from 1995 to 2020, yet desertification risk remains severeWater resources comprise 51.36% of all drivers and are the key to the world oasis's growthIn developing countries oases, climate (climate variability and climate change) will increase the demand for water resources [ABSTRACT FROM AUTHOR]

Abstract The human‐environmental system in drylands is centered on oases. Despite its extent and socio‐ecological importance, understanding the dynamic changes of global oases and their human and environmental driving forces is imperative for sustainable development in drylands under global warming. Nevertheless, the dynamic changes of global oases and how they respond to the evolving environment are not well established. In this study, three criteria were summarized (i.e., existing in dryland climates, surrounded or partially surrounded by desert terrain, having a reliable source of freshwater and forming landscape units with higher vegetation coverage/productivity). A global oasis distribution map from 1995 to 2020 was generated using European Space Agency Climate Change Initiative Land Cover and GIMMS‐3G+ data (overall accuracy within a 95% confidence interval is 0.85 ± 0.01) based on overlay analysis and visual interpretation. In addition, we used geographic and temporal weighted regression methods to evaluate the potential macro‐level elements affecting both global and local oasis growth. The result showed that the global oases area in 2020 occupied an area of 191.91 Mha, and most oases existed in Asia (77.3%). The global oases area has significantly increased from 1995 to 2020 (+8.65 Mha). However, about 13.43 Mha of the global oases are desertified, indicating a high risk of desertification. Water resources, contributing 51.36% to the total driver's contribution, are key to the global oasis expansion. In the context of climate (climate variability and climate change), this research highlights the need for improved holistic water resource management for long‐term global oasis growth, particularly in developing countries where the oases' development is threatened by water scarcity and desertification.

Abstract Understanding the impact of smartphone‐based multimodal information (SMMI) on travellers' P&R (park‐and‐ride) choice behaviour is very limited so far. The purpose of this study is to better understand how SMMI, social network information, and individual characteristics influence travellers' mode choices. A stated preference experiment consisting of one P&R option and two auto‐driving routes was conducted to collect car commuters’ P&R choice data in Shanghai, China. The panel mixed logit model was utilized to determine the influencing factors. It was found that the panel mixed logit model, accounting for correlations among repeated observations of the same respondent and random taste, significantly outperforms the cross‐sectional multinomial logit model in terms of goodness‐of‐fit. Specifically, travellers are highly sensitive to the information offered by SMMI on travel time, parking fare, and crowding level in subway cars, and heterogeneities do exist in travellers' preferences for these factors. In terms of social network information, the positive propensity of online reviews and information about P&R play a positive role in P&R promotion. In addition, individual characteristics including gender, age, occupation, years of driving, and P&R experience all contribute to explaining the choice of P&R. Finally, the elasticity analysis reveals that commuters are more satisfied with P&R time than with car time, and the cross elasticity of P&R time demonstrates a limited substitution effect of P&R on private cars.

Cross-sectional studies show that habitual use of alcohol is associated with severity of alcohol dependence reflected across a range of domains and lower number of detoxifications in multiple settings. In this study, we investigated whether alcohol use disorder (AUD) patients with greater habitual use of alcohol at baseline showed worse outcomes after one year of follow-up. A sample of inpatients with Diagnostic and Statistical Manual of Mental Disorders , Fourth Edition (DSM-IV) alcohol use disorder (AUD) was assessed at baseline (n = 50) and after one year (n = 30). The Habit, Reward, and Fear Scale (HRFS) was employed to quantify affective (fear or reward) and non-affective (habitual) drives for alcohol use, the Alcohol Dependence Scale (ADS) was used to assess clinical outcomes, and the Depression, Anxiety and Stress Scale (DASS-21) was used to quantify and control for associated affective symptoms. There was a significant reduction in the three HRFS scores at the follow-up. Regression analyses demonstrated that greater habit- and fear-related drives at baseline predicted greater decreases in the ADS scores at the endpoint. However, after controlling for age, sex and affective symptoms, only reward and fear were associated with reductions in ADS scores at the end of one year. Prescriptions of naltrexone and antidepressants/benzodiazepines did not predict decreases in reward and fear-related motivations. Although we were unable to confirm that habitual subscores at baseline predict worse long-term outcomes among inpatients with AUD, we found that a greater fear and reward motives for the use of alcohol predicted a greater magnitude of improvement in the AUD symptoms after one year. We hope that these findings will help develop new approaches toward AUD treatment and inform models of addiction research. [ABSTRACT FROM AUTHOR]

Parasitoids in the genus Lysiphlebus specialize on ant-tended aphids and have previously been reported to mimic the cuticular hydrocarbon (CHC) profiles of their aphid hosts to avoid detection by ants. However, the precise mechanisms that mediate reduced ant aggression toward Lysiphlebus spp. are not known, nor is it clear whether such mechanisms are broadly effective or specialized on particular aphid hosts. Here we explore the effects of wasp genotype and host environment on Lysiphlebus CHC profiles and ant aggression. Rearing asexual Lysiphlebus lines in different host aphid environments revealed effects of both wasp line and aphid host on wasp CHCs. However, variation in genotype and host affected different features of the CHC profile, with wasp genotype explaining most variation in linear and long-chain methyl alkanes, while aphid host environment primarily influenced short-chain methyl alkanes. Subsequent behavioural experiments revealed no effects of host environment on ant aggression, but strong evidence for genotypic effects. The influence of genotypic variation on experienced ant aggression and relevant chemical traits is particularly relevant in light of recent evidence for genetic divergence among Lysiphlebus parasitoids collected from different aphid hosts. [ABSTRACT FROM AUTHOR]

Understanding the impact of smartphone‐based multimodal information (SMMI) on travellers' P&R (park‐and‐ride) choice behaviour is very limited so far. The purpose of this study is to better understand how SMMI, social network information, and individual characteristics influence travellers' mode choices. A stated preference experiment consisting of one P&R option and two auto‐driving routes was conducted to collect car commuters' P&R choice data in Shanghai, China. The panel mixed logit model was utilized to determine the influencing factors. It was found that the panel mixed logit model, accounting for correlations among repeated observations of the same respondent and random taste, significantly outperforms the cross‐sectional multinomial logit model in terms of goodness‐of‐fit. Specifically, travellers are highly sensitive to the information offered by SMMI on travel time, parking fare, and crowding level in subway cars, and heterogeneities do exist in travellers' preferences for these factors. In terms of social network information, the positive propensity of online reviews and information about P&R play a positive role in P&R promotion. In addition, individual characteristics including gender, age, occupation, years of driving, and P&R experience all contribute to explaining the choice of P&R. Finally, the elasticity analysis reveals that commuters are more satisfied with P&R time than with car time, and the cross elasticity of P&R time demonstrates a limited substitution effect of P&R on private cars. [ABSTRACT FROM AUTHOR]

In the direct drive motion system, there are obvious feedback harmonics caused by the various disturbances, which have important influence on the thrust characteristics of the permanent magnet synchronous linear motor (PMSLM). This paper presents the influence of the feedback harmonics on the detent force for the direct drive motion system. Firstly, the Maxwell's equation and the Schwarz–Christoffel (SC) mapping‐based method are used to accurately establish the magnetic field model in the air‐gap considering the slotting effect and end effect. Then, based on the control model of the motion system, the drive current caused by the feedback harmonics are calculated considering the non‐linearity of the drive circuit. The detent force of PMSLM is analytically represented and analyzed. Finally, the validity of the theoretical analysis is verified by the finite‐element method (FEM) and experiments. The results shown that the feedback harmonics will be coupled with the detent force and intensify the couplings among different sources of the thrust harmonics, which will lead to new coupled thrust harmonics, deteriorating the dynamic precision of the direct drive motion system. [ABSTRACT FROM AUTHOR]

Frustration is an unpleasant emotion prevalent in several target applications of affective computing, such as human-machine interaction, learning, (online) customer interaction, and gaming. One idea to redeem this issue is to recognize frustration to offer help or mitigation in real-time, e.g., by a personal assistant. However, the recognition of frustration is not limited to these applied contexts but can also inform emotion research in general. This paper presents a dataset of 43 participants who experienced frustration in driving-related situations in a simulator. The data set contains a continuous subjective label, hand-annotated face and body expressions, facial landmark coordinates of two cameras, and the participants’ age and sex information. In addition, a descriptive analysis and description of the data's characteristics are provided together with a Graph Convolution Network based model to recognize frustration. Allowing for a tolerance of 10%, the model could correctly identify frustration with a similarity of 79.4 % and a variance of 7.7 %. This work is valuable for researchers of the affective computing community because it provides realistic data with an in-depth description of its characteristics and a benchmark model for automated frustration recognition. Our FRUST-dataset is publicly available under: https://ts.dlr.de/data-lake/frust-dataset/dataset.zip. [ABSTRACT FROM AUTHOR]

Despite drives' importance for Nietzsche's explanation of individuals' values, controversies persist over how to interpret Nietzsche's attribution of normative capacities to the drives themselves. On one reading, drives evaluate their aims and recognize the normative authority of other drives' aims. On another, drives' normative properties reduce to nonnormative, causal properties. Neither approach is satisfying. The former commits Nietzsche to the homuncular fallacy by granting drives complex cognitive capacities. The latter reading either commits Nietzsche to the naturalistic fallacy, having him derive normative conclusions from descriptive premises, or eliminates normativity from his thought altogether. In response to this impasse, this article advances a Leibniz-informed interpretation of Nietzsche's drive psychology. By construing the normative and efficient causal orders as parallel modes of explanation distinguished by one's perspective, a Leibniz-informed reading captures the benefits of extant interpretations while avoiding their drawbacks. [ABSTRACT FROM AUTHOR]

The rapid growth of energy demand requires progressive energy generation. This, together with the demand for higher efficiency and flexibility, has promoted the application of power electronics in energy systems. During the past decade, model predictive control (MPC) of power electronics has witnessed significant advancements in both dynamic performance and optimal control of the multi-objective terms. Several of these terms can have equal control priorities, resulting in a symmetrical cost function; however, most objectives have different priorities and require weighting factors to resolve the asymmetry in the cost function. Currently, researchers continue to encounter challenges in the optimal design of weighting factors. Moreover, the relative performance of different techniques that either utilize or avoid the weighting factor are uncertain. Therefore, this study focuses on weighting factor design techniques in the literature as applied to wind/solar energy conversion, microgrids, grid-connected converters, and other high-performance converter-based systems. These are grouped under the heuristic, offline tuning, sequential, and online optimization methods. This study demonstrates that optimal online tuning of weighting factors and sequential MPC methods can both offer improved robustness against parameter uncertainties. In addition, the advantages and limitations of different techniques are highlighted. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) is recently emerging as an efficient and promising technique for the control of power converters. In the conventional MPC algorithm, the control objectives are usually estimated and evaluated for a large/definite number of switching states. Since prediction and evaluation are done for all possible states, massive amounts of estimations are needed, moreover, the computational burden is more challenging with the increase of control objectives. In this paper, a computationally efficient version of the finite control set-MPC (FCS-MPC) is proposed to decrease the calculation effort of the MPC algorithm likewise minimizing its execution time to enforce its vast application for the control of three-phase power converters. The suggested procedure is to eliminate the current predictions as well as reduce the number of available switching states that need to be estimated by the algorithm which reduces considerably the amount of time consumed by these computations. The studied techniques achieved nearly the same performance with an interesting reduction in the algorithm execution time accomplished by the proposed modified FCS-MPC algorithms.

Celine published Voyage au bout de la nuit in 1932 and Mort à credit in 1936, two works that marked a turning point in modern literature after the Second World War. This study analyses the forms through which the drives manifest themselves, especially that Celine considered Freud as: “our great master of all.” In fact, the writer found in Freudian subjects and concepts a new vision that adhered to his experience of life including war, sexuality, death that are part of it. On the one hand, this study brings out the dimensions of the war, which is an initiating theme in the Celinian narration through the violence of the death drive, constantly present in the work, and on the second hand, it centers on the sexual drive which neither morals nor disease, in the midst of war, hindered. Finally, this analysis of the instinctual world is completed by highlighting the forms of delirium.

After reconstructing three arguments for Nietzsche's descriptive analysis of the self as complex, this article clarifies some of greatness's psychological conditions. It then offers three arguments for why we should not focus on these internal conditions when seeking to verify or to achieve greatness. First, Nietzsche's descriptive analysis of the self renders introspection too coarse-grained and error-prone to verify the subtle type of unity required for greatness. Second, Nietzsche associates introspective appraisal of one's psyche with a moral project that weakens and represses the drives, such that inquiry into whether greatness's internal conditions are satisfied typically speaks against their realization. Finally, the actions characteristic of Nietzsche's great individuals prohibit introspective preoccupation with oneself. These arguments suggest that we should attend to outwardly directed accomplishments, rather than psychology, when appraising the greatness of others and seeking to become great ourselves. [ABSTRACT FROM AUTHOR]

Primal repression, D.: Urverdrängung, is a concept belonging to the realm of metapsychological necessities, of the first structuralisation and construction of the mental system. It was postulated by Freud (1911, 1915, 1926, 1937) to retrospectively explain the mechanism of repression (repression proper) as a movement of attraction by something which is already there. Contrary to repression proper/secondary repression, D.: Nachdrängen, the “cornersone” of psychoanalytic thinking, the concept of primal repression stays partly forgotten, partly incomprehensible, even though its underlying conceptualisations have been attracting increased attention over the years. This paper approaches that realm by investigating representability and unrepresentable, dynamic: action – representation, and the birth of psychic from the requirements of work. The first internal duality and the first bond are introduced into psychic life by the processes of primal repression, a tension between regressive attraction and the formation-reconstruction of psychic processes. Clinical material is presented as an illustration. [ABSTRACT FROM AUTHOR]

This paper proposes a re-interpretation of the idea of Body in Nietzsche's philosophy to distinguish it from two important perspectives of Nietzsche-studies in Spanish: The first one maintains that the Body is comparable with Nature, and the second one, states that the Body is a cause of subjectivity. Analyzing part of Nietzsche's work after 1885 --published and unpublished-- shows that the idea of the Body works as a methodology that allows Nietzsche to accomplish a new task of his philosophy, such as the task of self-knowledge. In this way, the Body in Nietzsche's philosophy, besides being an innovative and redeemable concept, is a performative tool that establishes new dimensions "in-between" human knowing and bodily experimentation. [ABSTRACT FROM AUTHOR]

This paper presents the a.c. input power factor problem of an Industrial drive connected to a DC motor load and operated either in the continuous or discontinuous inductor current mode. This research became necessary in view of the Federal Government of Nigeria’s growing interest in the rail transport system and the likelihood of deploying Electric trains in the future. It begins with an in - depth mathematical analysis of the drive system and its performance factors such as: Harmonic factor (HF), Displacement factor (DF), Power factor (PF). The result shows the non – sinusoidal a.c input current in both the continuous and discontinuous current mode with high lower order harmonics.

Electric vehicles (EVs) are emerging as an alternative transportation system owing to a reduction in depleting lubricates usage and greenhouse gas emissions. This paper presents a technical review of each and every sub-system and its feasible control of battery EV (BEV) propulsion units. The study includes the possible combination of electrical machines (EMs), storage system, and power electronic converters and their associated control strategies. The primary unit, i.e., EM, is the heart of the EV, which is used to drive the vehicle at the desired speed as well as to restore the regenerative braking (RB) energy that is generated to enhance the overall system reliability. To electrify the transportation sector, it is necessary to include new options of power electronic converter topologies and their associated control strategies for numerous reasons, which include extracting maximum power from sources in case the EV is powered from renewable energy resources, boosting the energy storage capability for longer electric range, managing power flow from the source to battery or battery to vehicle or vehicle to battery, and regulating the speed of the vehicle and braking control. Based on the survey, the suitable combination of sub-systems and their control for three and four-wheeler EVs are summarized in this paper. [ABSTRACT FROM AUTHOR]

This article presents an analytical derivation of transient performance deterioration for high-speed surface-mounted permanent magnet synchronous machine (SPMSM) drives under parameter mismatches, with an advanced deadbeat predictive current control (DBPCC), which exhibits fast dynamics and strong robustness with disturbances rejection. All the influential factors, including permanent magnet flux linkage and inductance mismatches, inverter nonlinearity, and speeds are taken into account in the analysis. It is shown that the transient performance with the advanced DBPCC is only dependent on inductance accuracy. Large transient overshoot and cross-coupling in the dq-axis currents at high speeds arise due to inductance mismatch. Based on the understanding gained through the analysis, a novel inductance identification method is also proposed in this article, which significantly improves the transient performance of high-speed SPMSM drives. The proposed online inductance identification method does not require signal injection, is nonintrusive, and can be easily implemented. By integrating the proposed method with the advanced DBPCC, the close-to-ideal deadbeat control can be achieved for high-speed SPMSM drives even in the presence of parameter mismatch and inverter nonlinearity. Both the analysis and proposed method have been validated experimentally on a prototype high-speed (30 000 r/min) SPMSM drive under various conditions. [ABSTRACT FROM AUTHOR]

The article provides a review of the designs of rolling bearings (given in modern literature, patents and author's certificates), including designs that improve the load capacity and durability of bearings, reduce their wear and provide bearing lubrication. [ABSTRACT FROM AUTHOR]

The elimination of periodic torque disturbance in permanent magnet synchronous machine (PMSM) drives is a multifrequency control task, and adding resonant parts to the controller has an impact on the robustness of the system. This article aims to address the torque-ripple reduction in PMSM drives for smooth speed control, where an extended harmonic state observer (EHSO) is designed for estimation and attenuation of the selective periodic disturbance. The defects of applying the conventional bandwidth-parameterization method to the harmonic disturbance observer are explored. To improve the disturbance-rejection capability and the relative stability, a pole-placement strategy is proposed and analyzed through sensitivity function, which can preserve the comparable dynamic performance as the conventional extended state observer at the low-frequency range. The proposed EHSO also features easy parameter tuning and a modular structure for multiple harmonic disturbance rejection. Finally, the proposed method is evaluated on a laboratory PMSM platform. [ABSTRACT FROM AUTHOR]

Abstract The considerable expansion of non‐linear loads with interharmonic currents characteristic such as induction furnace, cycloconverter and variable‐speed drive is one of the new and important challenges in the control of industrial microgrids. For this reason, this paper presents an enhanced control scheme that tries to share power and especially interharmonic currents through parallel inverters accurately, which is not addressed in previous literature. In this regard, assuming the inherent delays of digital control, the proposed control strategy firstly suppresses the inherent impedances of inverters, especially in interharmonic frequencies. Then, the enhanced impedance‐power (I‐P) droop scheme is employed based on virtual inductors to compensate for the mismatch of line impedances and to achieve proper power‐sharing. Besides, novel techniques are introduced in the proposed structure to limit the values of virtual inductances and even to benefit from the negative virtual impedance method. The notable feature of the presented scheme is the sharing of interharmonic currents with high accuracy and low computations. Finally, the effectiveness of the proposed method is evaluated through simulation and experimental results.

Abstract For the dual three‐phase permanent magnet synchronous motor(dual‐PMSM), the deadtime can introduce fifth and seventh current harmonics, and they are only constrained by the small stator leakage impedance, which means even if there are only small fifth and seventh voltage harmonics, the resulting fifth and seventh current harmonics will be very large. The harmonic current will make an increment of the system loss, thus lead to an reduce of the efficiency of the speed control system. This paper proposes a harmonic current suppression strategy for dual‐PMSM based on least mean square (LMS) adaptive notch filter. This strategy suppresses the fifth and seventh harmonic currents by introducing four LMS adaptive notch filters in the subspace. The proposed algorithm has good dynamic performance and is insensitive to motor parameters that are offset within a certain range. The effectiveness of proposed method is verified by a set of comparative simulations and experiments.

Abstract Permanent magnet machines have been used in the high‐speed drive applications due to their high‐efficiency, high‐power‐density, and wide‐speed range characteristics. However, control of such high‐speed permanent magnet machines machine is always challenging and proper flux‐weakening controller design is essential to achieve high performance of these machines. In this paper, an improved feedforward flux‐weakening control scheme for interior permanent magnet synchronous machine (IPMSM) drives are proposed. The proposed method identifies optimal d‐axis and q‐axis currents under different operation regions using maximum‐torque‐per‐ampere curve, voltage limit, and current limit curves with a fast Newton–Raphson algorithm. To ensure the optimal performance of the control mechanism, effects of inductance variations due to the magnetic saturation are considered and an innovative high‐frequency staircase voltage injection method is used to identify the q‐axis inductance. The experimental results show that compared with other existing flux‐weakening methods, the proposed technique can improve the DC‐link voltage utilisation without the need to tune any controller gains and can fully utilise maximum available torque with desirable transient performance.

BackgroundThe present study aims to investigate one of the major causes of traffic accidents: drivers' unsafe behaviors while driving.MethodsIn this cross-sectional study, the behaviors of 946 drivers at traffic lights were observed in the morning, at noon, and in the evening using direct in-field observation. The unsafe behaviors of the drivers included not fastening the seat belt, using a cellphone or handsfree device, smoking, being distracted by a child, talking with passengers, not observing the stop line, eating and drinking, and getting out of the car, letting out a passenger, or arguing with a passenger at the traffic light.ResultsOf the drivers at the traffic light, 60% did not obey the stop line, and 72% did not fasten their seat belt. Also, 13.6% used their cellphones, and 22% talked with passengers. The frequency of the other unsafe behaviors was

The paper provides an overview of the designs of cogwheels contained in modern literature, patents, and inventor certificates. Structures are described that make it possible to ensure the dismantling of wheels, reduce contact stresses, and increase the durability and bearing capacity of the wheels. [ABSTRACT FROM AUTHOR]