Асинхронный электропривод винтового компрессора

Объектом исследования является винтовой компрессор для подачи сжатого воздуха в пневмооборудовании. В данной работе произведён расчет по выбору электропривода и преобразователя частоты для управления винтовым компрессором. Обоснован выбор способа управления, рассчитаны механические и электромеханические характеристики. Методом имитационного моделирования на ЭВМ исследованы переходные процессы, сделаны выводы и обобщения по результатам моделирования и расчета.The object of the study is a screw compressor for supplying compressed air in pneumatic equipment. In this paper, the choice of the electric drive and the frequency converter for controlling the screw compressor was calculated. The choice of the control method is substantiated, mechanical and electromechanical characteristics are calculated. The method of simulation on a computer studied transient processes, conclusions and generalizations based on the results of modeling and calculation

Dissociations in semantic cognition : Oscillatory evidence for opposing effects of semantic control and type of semantic relation in anterior and posterior temporal cortex

How does the brain represent and process different types of knowledge? The Dual Hub account postulates that anterior temporal lobes (ATL) support taxonomic relationships based on shared physical features (mole – cat), while temporoparietal regions, including posterior middle temporal gyrus (pMTG), support thematic associations (mole – earth). Conversely, the Controlled Semantic Cognition account proposes that ATL supports both aspects of knowledge, while left pMTG contributes to controlled retrieval. This study used magnetoencephalography to test these contrasting predictions of functional dissociations within the temporal lobe. ATL and pMTG responded more strongly to taxonomic and thematic trials respectively, matched for behavioural performance, in line with predictions of the Dual Hub account. In addition, ATL showed a greater response to strong than weak thematic associations, while pMTG showed the opposite pattern, supporting a key prediction of the Controlled Semantic Cognition account. ATL showed a stronger response for word pairs that were more semantically coherent, either because they shared physical features (in taxonomic trials) or a strong thematic association. These effects largely coincided in time and frequency (although an early oscillatory response in ATL was specific to taxonomic trials). In contrast, pMTG showed non-overlapping effects of semantic control demands and thematic judgements: this site showed a larger oscillatory response to weak associations, when ongoing retrieval needed to be shaped to suit the task demands, and also a larger response to thematic judgements contrasted with taxonomic trials (which was reduced but not eliminated when the thematic trials were easier). Consequently, time-sensitive neuroimaging supports a complex pattern of functional dissociations within the left temporal lobe, which reflects both coherence versus control and distinctive oscillatory responses for taxonomic overlap (in ATL) and thematic relations (in pMTG)

Dissociation between Semantic Representations for Motion and Action Verbs: Evidence from Patients with Left Hemisphere Lesions

This multiple single case study contrasted left hemisphere stroke patients (N = 6) to healthy age-matched control participants (N = 15) on their understanding of action (e.g., holding, clenching) and motion verbs (e.g., crumbling, flowing). The tasks required participants to correctly identify the matching verb or associated picture. Dissociations on action and motion verb content depending on lesion site were expected. As predicted for verbs containing an action and/or motion content, modified t-tests confirmed selective deficits in processing motion verbs in patients with lesions involving posterior parietal and lateral occipitotemporal cortex. In contrast, deficits in verbs describing motionless actions were found in patients with more anterior lesions sparing posterior parietal and lateral occipitotemporal cortex. These findings support the hypotheses that semantic representations for action and motion are behaviorally and neuro-anatomically dissociable. The findings clarify the differential and critical role of perceptual and motor regions in processing modality-specific semantic knowledge as opposed to a supportive but not necessary role. We contextualize these results within theories from both cognitive psychology and cognitive neuroscience that make claims over the role of sensory and motor information in semantic representation

Interactive Experiences Shape the Perception of an Artistic Performance: Evidence from Eye Movements and Physiological Measures

The present study investigates the impact of different interventions on the gaze patterns and physiological reactions of observers during the perception of Sediments, an abstract dynamic art work performed by the artist The Baltazars. Thirty-four participants watched the performance before and after participating in one of three interventions: one involving direct manipulation of the visual effects of the show via a tactile interface, one involving verbal exchanges about the performance, and one unrelated to the performance. Eye movements and electrodermal activity were recorded during the two exposures to the show. Results showed that the two interventions focusing on the show impacted visual exploration and physiological responses, beyond the effect of repeated exposure. Participating in an activity related to the artistic performance increased visual exploration and emotional arousal. In addition, interventions changed visual exploration in different ways depending on their content. Verbal exchanges led to a global visual exploration of the artistic performance whereas manipulation of the visual effects of the show led to a more local visual exploration of the show. Together, findings demonstrate that interactive experiences can modify the subsequent perception of an artistic performance