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1.
Heliyon ; 10(13): e33227, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39050441

RESUMO

The paper deals with some peculiar aspects of the design of interleaved voltage source converter (IVSC) topology in high-power applications such as renewable energy systems and electric vehicles. The IVSC offers advantages like power sharing among multiple modules, improved power quality, redundancy, and fault tolerance. The design of an IVSC mainly involves the selection of the number of deployed converters and the choice of suitable semiconductor devices with the aim to reach a desired overall efficiency for an assigned operating condition. The paper develops an approach to characterize through a straightforward procedure the dependence of the IVSC' power losses on the number of the interlaced converters, on the employed semiconductor devices used and on a properly conceived set of key parameters which define the system operating conditions. The proposed methodology allows to highlight the system performance' dependence on the chosen power devices and it is showcased in this work by considering silicon carbide (SIC) devices with different current ratings. The main goal of the paper is to formulate a smart design procedure able to guide the configuration of an IVSC towards an optimal choice with respect to the power module rating, the number of interleaved levels, the system efficiency, and the output current waveforms. The proposed procedure has been experimentally validated.

2.
Sci Rep ; 14(1): 14977, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38951160

RESUMO

Enhancing the efficiency of the electric vehicle's powertrain becomes a crucial focus, wherein the control system for the traction motor plays a significant role. This paper presents a novel electric vehicle traction motor control system based on a robust predictive direct torque control approach, an improved version of the conventional DTC, where the traditional switching table and the hysteresis regulators are substituted with a predictive block based on an optimization algorithm. Additionally, a robust predictive speed loop regulator is employed instead of the proportional-integral regulator, which integrates a new cost function with a finite horizon, incorporating integral action into the control law based on a Taylor series expansion. This technique's primary benefit is its independence from the necessity to measure and observe external disturbances, as well as uncertainties related to parameters. The effectiveness of the suggested system was confirmed through simulation and experimental results under the OPAL-RT platform. The findings indicate that the proposed approach outperforms the conventional method in terms of rejecting disturbances, exhibiting robustness to variations in parameters, and minimizing torque ripple.

3.
Sensors (Basel) ; 24(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38894327

RESUMO

Advancements in machining technology demand higher speeds and precision, necessitating improved control systems in equipment like CNC machine tools. Due to lead errors, structural vibrations, and thermal deformation, commercial CNC controllers commonly use rotary encoders in the motor side to close the position loop, aiming to prevent insufficient stability and premature wear and damage of components. This paper introduces a multivariable iterative learning control (MILC) method tailored for flexible feed drive systems, focusing on enhancing dynamic positioning accuracy. The MILC employs error data from both the motor and table sides, enhancing precision by injecting compensation commands into both the reference trajectory and control command through a norm-optimization process. This method effectively mitigates conflicts between feedback control (FBC) and traditional iterative learning control (ILC) in flexible structures, achieving smaller tracking errors in the table side. The performance and efficacy of the MILC system are experimentally validated on an industrial biaxial CNC machine tool, demonstrating its potential for precision control in modern machining equipment.

4.
Transfusion ; 64(5): 881-892, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38591151

RESUMO

BACKGROUND: A life-threatening anaphylactic shock can occur if a patient with undiagnosed immunoglobulin A (IgA) deficiency (i.e., IgA levels <500 ng/mL) receives IgA-containing blood, hence the need for a rapid, point-of-care (POC) method for IgA deficiency screening. Enzyme-linked immunosorbent assay (ELISA) is routinely used to detect IgA, but this method requires trained specialists and ≥24 h to obtain a result. We developed a surface plasmon resonance (SPR)-based protocol to identify IgA-deficient patients or donors within 1 h. MATERIALS AND METHODS: The SPR sensor relies on the detection of IgAs captured by primary antibodies adsorbed on the SPR chip and quantified with secondary antibodies. The sensor was calibrated from 0 to 2000 ng/mL in buffer, IgA-depleted human serum, and plasma samples from IgA-deficient individuals. A critical concentration of 500 ng/mL was set for IgA deficiency. The optimized sensor was then tested on eight plasma samples with known IgA status (determined by ELISA), including five with IgA deficiency and three with normal IgA levels. RESULTS: The limit of detection was estimated at 30 ng/mL in buffer and 400 ng/mL in diluted plasma. The results obtained fully agreed with ELISA among the eight plasma samples tested. The protocol distinguished IgA-deficient from normal samples, even for samples with an IgA concentration closer to critical concentration. DISCUSSION: In conclusion, we developed a reliable POC assay for the quantification of IgA in plasma. This test may permit POC testing at blood drives and centralized centers to maintain reserves of IgA-deficient blood and in-hospital testing of blood recipients.


Assuntos
Deficiência de IgA , Imunoglobulina A , Ressonância de Plasmônio de Superfície , Humanos , Ressonância de Plasmônio de Superfície/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Imunoglobulina A/sangue , Deficiência de IgA/sangue , Deficiência de IgA/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos
5.
Pest Manag Sci ; 80(6): 2950-2964, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38344908

RESUMO

BACKGROUND: One of the proposed applications of gene drives has been to revert pesticide resistant mutations back to the ancestral susceptible state. Insecticides that have become ineffective because of the rise of resistance could have reinvigorated utility and be used to suppress pest populations again, perhaps at lower application doses. RESULTS: We have created a laboratory model for susceptibility gene drives that replaces field-selected resistant variants of the acetylcholine esterase (Ace) locus of Drosophila melanogaster with ancestral susceptible variants. We constructed a CRISPR/Cas9 homing drive and found that homing occurred in many genetic backgrounds with varying efficiencies. While the drive itself could not be homozygous, it converted resistant alleles into susceptible ones and produced recessive lethal alleles that could suppress populations. Our studies provided evidence for two distinct classes of gene drive resistance (GDR): rather than being mediated by the conventional non-homologous end-joining (NHEJ) pathway, one seemed to involve short homologous repair and the other was defined by genetic background. Additionally, we used simulations to explore a distinct application of susceptibility drives; the use of chemicals to prevent the spread of synthetic gene drives into protected areas. CONCLUSIONS: Insecticide susceptibility gene drives could be useful tools to control pest insects however problems with particularities of target loci and GDR will need to be overcome for them to be effective. Furthermore, realistic patterns of pest dispersal and high insecticide exposure rates would be required if susceptibility were to be useful as a 'safety-switch' to prevent the unwanted spread of gene drives. © 2024 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Acetilcolinesterase , Drosophila melanogaster , Tecnologia de Impulso Genético , Resistência a Inseticidas , Animais , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Sistemas CRISPR-Cas , Drosophila melanogaster/genética , Drosophila melanogaster/efeitos dos fármacos , Proteínas de Drosophila/genética , Resistência a Inseticidas/genética , Inseticidas/farmacologia
6.
Elife ; 122023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38051195

RESUMO

Lipophorin is an essential, highly expressed lipid transport protein that is secreted and circulates in insect hemolymph. We hijacked the Anopheles coluzzii Lipophorin gene to make it co-express a single-chain version of antibody 2A10, which binds sporozoites of the malaria parasite Plasmodium falciparum. The resulting transgenic mosquitoes show a markedly decreased ability to transmit Plasmodium berghei expressing the P. falciparum circumsporozoite protein to mice. To force the spread of this antimalarial transgene in a mosquito population, we designed and tested several CRISPR/Cas9-based gene drives. One of these is installed in, and disrupts, the pro-parasitic gene Saglin and also cleaves wild-type Lipophorin, causing the anti-malarial modified Lipophorin version to replace the wild type and hitch-hike together with the Saglin drive. Although generating drive-resistant alleles and showing instability in its gRNA-encoding multiplex array, the Saglin-based gene drive reached high levels in caged mosquito populations and efficiently promoted the simultaneous spread of the antimalarial Lipophorin::Sc2A10 allele. This combination is expected to decrease parasite transmission via two different mechanisms. This work contributes to the design of novel strategies to spread antimalarial transgenes in mosquitoes, and illustrates some expected and unexpected outcomes encountered when establishing a population modification gene drive.


Assuntos
Anopheles , Antimaláricos , Tecnologia de Impulso Genético , Lipoproteínas , Animais , Camundongos , Anopheles/genética , Anopheles/parasitologia , Antimaláricos/farmacologia , Mosquitos Vetores/genética , RNA Guia de Sistemas CRISPR-Cas , Plasmodium falciparum/genética , Plasmodium berghei/genética
7.
Micromachines (Basel) ; 14(12)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38138399

RESUMO

This paper investigates how the electromechanical response of MEMS/NEMS devices changes when the geometrical characteristics of their embedded flexural hinges are modified. The research is dedicated particularly to MEMS/NEMS devices which are actuated by means of rotary comb-drives. The electromechanical behavior of a chosen rotary device is assessed by studying the rotation of the end effector, the motion of the comb-drive mobile fingers, the actuator's maximum operating voltage, and the stress sustained by the flexure when the flexure's shape, length, and width change. The results are compared with the behavior of a standard revolute joint. Outcomes demonstrate that a linear flexible beam cannot perfectly replace the revolute joint as it induces a translation that strongly facilitates the pull-in phenomenon and significantly increases the risk of ruptures of the comb-drives. On the other hand, results show how curved beams provide a motion that better resembles the revolute motion, preserving the structural integrity of the device and avoiding the pull-in phenomenon. Finally, results also show that the end effector motion approaches most precisely the revolute motion when a fine tuning of the beam's length and width is performed.

8.
J Psychiatr Res ; 168: 263-268, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37891039

RESUMO

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.


Assuntos
Alcoolismo , Humanos , Alcoolismo/psicologia , Estudos Prospectivos , Motivação , Estudos Transversais , Recompensa , Medo , Hábitos , Manual Diagnóstico e Estatístico de Transtornos Mentais
9.
Proc Biol Sci ; 290(2009): 20231642, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37848063

RESUMO

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.


Assuntos
Formigas , Afídeos , Vespas , Animais , Afídeos/genética , Hidrocarbonetos , Vespas/genética , Alcanos , Agressão , Genótipo
10.
Int J Psychoanal ; 104(4): 775-788, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37732728

RESUMO

In this paper, the authors explore the depiction of perversion and the associated interplay of life and death drives in Roman Polanski's 1992 film Bitter Moon. To begin with, a theoretical discussion is presented regarding perverse organizations of mastery and sadomasochism. Perversion is viewed as an expression of the death drive under erotic disguise, in which the destructive fingerprint of the death drive is revealed at every stage, having as its ultimate purpose the destruction of the other. Based on these theoretical insights a dialogue is developed with Polanski's film, which brings to life the theory of sadomasochistic relations through the multidimensional aesthetic medium of cinema. It is shown how Polanski's cinematic oeuvre conveys the essence of the difficult and complex experience of perverse relations, where the life and death drives and their transformations are manifested. The portrayal of the sadomasochistic relations in this film contributes to the experiential knowledge with which the authors promote insight that would potentially enrich the clinical work with patients with perverse organizations.


Assuntos
Ódio , Filmes Cinematográficos , Humanos , Estética , Conhecimento
11.
Psychodyn Psychiatry ; 51(3): 254-260, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37712662

RESUMO

Psychoanalysis has long lost its historical influence on U.S. academic psychiatry. Psychoanalytic theory, however, provides us with a rich and remarkably comprehensive knowledge of human development, both normative and pathologic. This article describes a psychoanalytic concept that enriches our understanding of the mind and its disorders: Freud's structural hypothesis. This core concept provides a theoretical foundation for understanding the clinical features of both neurotic and personality disorders. It also informs a psychodynamic psychotherapy.


Assuntos
Psiquiatria , Psicanálise , Psicoterapia Psicodinâmica , Humanos , Transtornos da Personalidade , Teoria Psicanalítica
12.
Sensors (Basel) ; 23(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37631591

RESUMO

The article presents the results of a developed model and experimental studies of the Minimess® hydraulic signal hose's influence on the changes in the indications of the pressure transducer during the high dynamics of hydrostatic drives and controls. The model test results show that measuring hoses can be used as hardware low-pass filters during the digital recording of pressure waveforms. However, the cut-off frequency values of the measuring hoses obtained using the model are dramatically lower than those observed during the experiment. The experiment results show that the measuring hoses can only be used without any limitations to measure the average pressure value. In the case of measuring pressure waveforms, the user should carefully choose the measuring hose length. For this reason, the relationship between the measuring hose length and its cut-off frequency should be known.

13.
Ecol Appl ; 33(7): e2912, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37615220

RESUMO

Gene drives offer a potentially revolutionary method for pest control over large spatial extents. These genetic modifications spread deleterious variants through a population and have been proposed as methods for pest suppression or even eradication. We examined the influence of local dispersal, long-distance and/or human-mediated dispersal, and variation in population growth on the success of a gene drive for the control of invasive social wasps (Vespula vulgaris). Our simulations incorporated a spatially realistic environment containing variable habitat quality in New Zealand. Pest eradication was not observed, except in extreme and unrealistic scenarios of constant, widespread, and spatially intense releases of genetically modified individuals every year for decades. Instead, the regional persistence of genetically modified and wild-type wasps was predicted. Simulations using spatially homogeneous versus realistic landscapes (incorporating uninhabitable areas and dispersal barriers) showed little difference in overall population dynamics. Overall, little impact on wasp abundance was observed in the first 15 years after introduction. After 25 years, populations were suppressed to levels <95% of starting populations. Populations exhibited "chase dynamics" with population cycles in space, with local extinction occurring in some areas while wasps became abundant in others. Increasing the wasps' local dispersal distance increased the spatial and temporal variability of the occupied area and population suppression. Varying levels of human-associated long-distance dispersal had little effect on population dynamics. Increasing intrinsic population growth rates interacted with local dispersal to cause higher mean populations and substantially higher levels of variation in population suppression and the total amount of landscape occupied. Gene drives appear unlikely to cause a rapid and widespread extinction of this and probably other pests but could offer long-term and cost-effective methods of pest suppression. The predicted level of <95% pest suppression would substantially reduce the predation pressure and competitive interactions of this invasive wasp on native species. However, the predicted long-term persistence of genetically modified pests will influence the ethics and likelihood of using gene drives for pest control, especially given concerns that modified wasps would eventually be transported back to their home range.


Assuntos
Tecnologia de Impulso Genético , Mariposas , Vespas , Humanos , Animais , Vespas/genética , Dinâmica Populacional , Ecossistema
14.
Sensors (Basel) ; 23(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37514806

RESUMO

A three-phase GaN-based motor inverter IC with three integrated phase current mirror sensors (sense-FETs or sense-HEMTs, 1200:1 ratio), a temperature sensor, and an amplifier is presented and experimentally operated. The three low-side currents are read out by virtual grounding transimpedance amplifiers. A modified summed DC current readout circuit using only one amplifier is also discussed. During continuous 24 V motor operation with space-vector pulse width modulation (SVPWM), the sensor signal is measured and a bidirectional measurement capability is verified. The measured risetime of the sensor signal is 51 ns, indicating around 7 MHz bandwidth (without intentional optimization for high bandwidth). The IC is operated up to 32 V on DC-biased semi-floating substrate to limit negative static back-gating of the high-side transistors to around -7% of the DC-link voltage. Analysis of the capacitive coupling from the three switch-nodes to the substrate is calculated for SVPWM based on capacitance measurement, resulting in four discrete semi-floating substrate voltage levels, which is experimentally verified. Integrated advanced power converter topologies with sensors improve the power density of power electronics applications, such as for low-voltage motor drive.

15.
Data Brief ; 48: 109154, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383744

RESUMO

This dataset covers 2476-2479 Polish municipalities and cities (dependent on the year) over a period from 2004 when Poland joined the EU to the pre-COVID-19-pandemic 2019. The created 113 yearly panel variables include budgetary, electoral competitiveness, and European Union funded investment drive data. While the dataset has been created out of publicly available sources, their use requires advanced knowledge of budgetary data and their classification, as well as data gathering, merging, and clearing, which required many hours of work over a year. Fiscal variables were created out of raw data of over 25 million subcentral governments records. They were sourced from Rb27s (revenue), Rb28s (expenditure), RbNDS (balance), and RbZtd (debt) forms, which are reported quarterly by all subcentral governments to the Ministry of Finance. These data were aggregated according to the governmental budgetary classification keys into ready-to-use variables. Furthermore, these data were used to create original EU-financed local investment drives proxy variables based on large investments in general and in sports objects in particular. Moreover, subcentral electoral data from 2002, 2006, 2010, 2014, and 2018 were sourced from the National Electoral Commission, mapped, cleared, merged, and used to create original electoral competitiveness variables. This dataset can be used to model different aspects of fiscal decentralization, political budget cycles, and EU-funded investment in a large sample of local government units.

16.
Bioethics ; 37(6): 600-609, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37133893

RESUMO

Despite widespread and worldwide efforts to eradicate vector-borne diseases such as malaria, these diseases continue to have an enormous negative impact on public health. For this reason, scientists are working on novel control strategies, such as gene drive technologies (GDTs). As GDT research advances, researchers are contemplating the potential next step of conducting field trials. An important point of discussion regarding these field trials relates to who should be informed, consulted, and involved in decision-making about their design and launch. It is generally argued that community members have a particularly strong claim to be engaged, and yet, disagreement and lack of clarity exist about how this "community" should be defined and delineated. In this paper, we shed light on this "boundary problem": the problem of determining how boundaries of inclusion and exclusion in (GDT) community engagement should be drawn. As our analysis demonstrates, the process of defining and delineating a community is itself normative. First, we explicate why it is important to define and delineate the community. Second, we demonstrate that different definitions of community are used and intermingled in the debate on GDTs, and argue in favor of distinguishing geographical, affected, cultural, and political communities. Finally, we propose initial guidance for deciding who should (not) be engaged in decision-making about GDT field trials, by arguing that the definition and delineation of the community should depend on the rationale for engagement and that the characteristics of the community itself can guide the effective design of community engagement strategies.


Assuntos
Tecnologia de Impulso Genético , Humanos , Participação da Comunidade , Saúde Pública , Pesquisadores , Dissidências e Disputas
17.
ISA Trans ; 139: 724-738, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37087306

RESUMO

The paper presents a novel control method based on a dual thread speed controller with modified multi-oscillatory control for speed ripple reduction in a switched reluctance machine-based drive. The method is based on on-line phase current shaping. The paper describes a dual thread angle-sampled multi-oscillatory control (ASMOSC) theory for speed ripple reduction of a switched reluctance machine under variable speed. Description of the entire cascaded speed control system with linear controllers is also provided, along with an implementation description for ASMOSC. This includes practical hints on how to apply the control system to a dual core microcontroller. The frequency-domain stability analysis for a designed control system under variable speed conditions is presented. The overall performance of the control system is verified numerically and experimentally on a laboratory setup with an 4-phase 8/6 SRM-based drive.

18.
mBio ; 14(1): e0317322, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36537809

RESUMO

Fungal spore killers are a class of selfish genetic elements that positively bias their own inheritance by killing non-inheriting gametes following meiosis. As killing takes place specifically within the developing fungal ascus, a tissue which is experimentally difficult to isolate, our understanding of the mechanisms underlying spore killers are limited. In particular, how these loci kill other spores within the fungal ascus is largely unknown. Here, we overcome these experimental barriers by developing model systems in 2 evolutionary distant organisms, Escherichia coli (bacterium) and Saccharomyces cerevisiae (yeast), similar to previous approaches taken to examine the wtf spore killers. Using these systems, we show that the Podospora anserina spore killer protein SPOK1 enacts killing through targeting DNA. IMPORTANCE Natural gene drives have shaped the genomes of many eukaryotes and recently have been considered for applications to control undesirable species. In fungi, these loci are called spore killers. Despite their importance in evolutionary processes and possible applications, our understanding of how they enact killing is limited. We show that the spore killer protein Spok1, which has homologues throughout the fungal tree of life, acts via DNA disruption. Spok1 is only the second spore killer locus in which the cellular target of killing has been identified and is the first known to target DNA. We also show that the DNA disrupting activity of Spok1 is functional in both bacteria and yeast suggesting a highly conserved mode of action.


Assuntos
Células Escamosas Atípicas do Colo do Útero , Tecnologia de Impulso Genético , Feminino , Humanos , Saccharomyces cerevisiae/genética , Genes Fúngicos , Esporos Fúngicos/genética , DNA , Meiose
19.
ISA Trans ; 134: 588-600, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36055823

RESUMO

A simplified inverter-motor stator system model is presented in the paper. The model is based on elementary dynamic blocks described by differential equations. The paper presents the results of research aimed at verifying the model on different devices with different types of inverters and motors. Model accuracy coefficients have been developed for all examined cases, confirming the high conformity of the model to the measured speeds and torques of asynchronous motors. The model was also used to simulate the operation of a drive system with a synchronous motor, obtaining high compliance of speed and torque mapping. The presented cases of verification of a simplified model confirm the possibility of using it to model different devices fed by frequency inverters, controlled both manually and automatically. The presented model, using simple description, ensures high accuracy of speed and torque mapping. It should be emphasized that most parameters in the presented model are calculated for motors and inverters based on data sheets.

20.
Front Public Health ; 10: 815380, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530723

RESUMO

Background: The present study aims to investigate one of the major causes of traffic accidents: drivers' unsafe behaviors while driving. Methods: In 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. Results: Of 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 <3%. For wearing seat belts, drivers aged 41-50 years wore seat belts almost five times more than drivers under 25 years of age (4.94 [2.36-10.320]; p < 0.001), and drivers aged 50 years and older were almost three times likelier to wear seat belts than drivers under 25 years of age (2.8 [1.31-6.08]; p < 0.001). The results showed that the drivers were significantly likelier to wear seat belts on Saturdays (after the weekend) (0.56 [0.40-0.78]; p = 0.001). Regarding using mobile phones while driving, women were twice as likely to use mobile phones as men (2.20 [1.30-3.72]; p < 0.001). Drivers aged 26-40 years used mobile phones significantly less than drivers under 25 years of age (0.24 [0.14-0.43]; p < 0.001) and drivers aged 41-50 years were significantly less likely to use mobile phones than drivers under 25 years of age (0.19 [1.31-6.08]; p < 0.001). Conclusion: The results showed that the occurrence of wearing a seat belt in Shahin Dej was low. We observed a significant association between wearing a seat belt, age, whether it was Saturday (a day after weekend for Iranians). Additionally, similar associations were observed between using mobile phones and gender, age, and day of the week.


Assuntos
Condução de Veículo , Cintos de Segurança , Criança , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Adulto , Irã (Geográfico)/epidemiologia , Estudos Transversais , Azerbaijão
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