A SOUNDNESS ANALYSIS OF ZENO’S OF ELEA DICHOTOMY

We are studying three basic interpretations of the Dichotomy aporia, in which Zeno tries to prove the impossibility of movement. In all these interpretations, the key assumption is the dubious statement about the impossibility of performing an infinite sequence of actions in a finite time. However, we show that in the two interpretations of the Dichotomy it is possible to get rid of the dubious key assumption, replacing it with the seemingly much more reliable assumption that covering the distance is representable as a sequence of displacements. Our approach is based on the thesis proved by P. Benacerraf that completing an infinite sequence of movements in an interpretation of the Dichotomy is not sufficient to arrive to the end of the distance.

Development and Implementation of an Anthropomorphic Underactuated Prosthesis with Adaptive Grip

This paper describes the design of a prosthetic hand for wrist amputations. The mechanism considers the use of three actuators: one each for the movement of the little finger, annular finger, and middle finger. The second actuator controls the index finger, and the third controls the thumb. The prototype is considered relevant as it is able to move the distal phalanx in all fingers; the little, annular, and middle fingers are able to adapt to the shape of the object being gripped (adaptive grip). The sequence of movements achieved with the thumb emulate the opposition/reposition and flexion/extension movements, commanded by a single actuator. The proposed design was built by additive manufacturing and effortlessly achieves a large number of grips. Additionally, the prosthesis could perform specific movements, such as holding a needle, although this grip demands higher precision in the control of the fingers. Due to the manufacturing method, the prosthesis weighs only 200 g, increasing to 450 g when the actuators are included, therefore weighing less than an average adult’s hand.

The basal ganglia corticostriatal loops and conditional learning

Brief maneuvering of the literature as to the various roles attributed to the basal ganglia corticostriatal circuits in a variety of cognitive processes such as working memory, selective attention, and category learning has inspired us to investigate the interplay of the two major basal ganglia open-recurrent loops, namely, visual and executive loops specifically the possible involvement of their overlap in conditional learning. We propose that the interaction of the visual and executive loops reflected through their cortical overlap in the dorsolateral prefrontal cortex (DL-PFC), lateral orbitofrontal cortex (LO-PFC), and presupplementary motor area (SMA) plays an instrumental role preliminary first in forming associations between a series of correct responses following similar stimuli and then in shifting, abstracting, and generalizing conditioned responses. The premotor and supplementary motor areas have been shown essential to producing a sequence of movements while the SMA is engaged in monitoring complex movements. In light of the recent studies, we will suggest that the interaction of visual and executive loops could strengthen or weaken learned associations following different reward values. Furthermore, we speculate that the overlap of the visual and executive loops can account for the switching between the associative vs. rule-based category learning systems.

An Analysis of the Traveling Speed in the Traveling Hoist Scheduling Problem for Electroplating Processes

The Hoist Scheduling Problem is combinatory, so tools such as mathematical programming need to be used to get the sequence of movements, respecting the constraints of the process by minimizing the cycle time. A sequence in which the order of movements follows the order of the process is known as the basic diagram. These schedules do not have any clearance for the hoist to make any other movements, resulting in a loss in productivity. This chapter takes the production line of a Mexican factory as a case study, analyzing the hoist's travelling speed to find sequences of movements that could improve productivity. The results of the study indicate that the cycle time has a nonlinear behavior in respect of the hoist's travelling speed and it was determined that there are travelling speeds for which sequences are obtained with enough clearance to make other movements and keep other carriers on the line. A suitable speed was estimated in the case.

Design principles for non-reciprocal photomechanical actuation

Non-reciprocal motions are a sequence of movements exhibiting time-reversal asymmetry. This work introduces design principles for non-reciprocal light-triggered actuation and self-oscillation.

Relationship between cardiac cycle and the timing of actions during action execution and observation

Previous research suggests that there may be a relationship between the timing of motor events and phases of the cardiac cycle. However, this relationship has thus far only been researched using simple isolated movements such as key-presses in reaction-time tasks and only in a single subject acting alone. Other research has shown both movement and cardiac coordination among interacting individuals. Here, we investigated how the cardiac cycle relates to ongoing self-paced movements in both action execution and observation using a novel dyadic paradigm. We recorded electrocardiography (ECG) in 26 healthy adult subjects who formed 19 dyads (7 comprised of two subjects and 12 subjects paired with an experimenter). Each dyad contained an action executioner and observer as they performed a self-paced sequence of movements. We demonstrated that heartbeats are timed to movements during both action execution and observation. Specifically, movements were less likely to culminate synchronously with the heartbeat, around the time of the R-peak of the ECG. The same pattern was observed for action observation, with the observers’ heartbeats occurring off-phase with movement culmination. These findings demonstrate that there is coordination between an action executioner’s cardiac cycle and the timing of their movements, and that the same relationship is mirrored in an observer. This suggests that previous findings of interpersonal coordination may be caused by the mirroring of a phasic relationship between movement and the heart.

Representing Multicultural Semarang through Gambang Semarang’s Narrative

Dance is usually perceived as a structured movement done by a person or more and accompanied by music and in some cases songs. The attention on physical movement often neglects the narrative which may exist behind a dance. Dances often have stories which frame the sequence of movements done by the dancers. The stories in a dance have elements of literature such as theme, plot, characters, and setting. This paper which is part of an on-going research on Semarang traditional dance discusses the story told through the movements and costume of Gambang Semarang dance. Gambang Semarang is traditional performing arts from Semarang which originally consists of music, vocal, dance, and comedy. Gambang Semarang dance was a small part of Gambang Semarang performance, but it is often performed separately from the complete performance now. The dance is commonly accompanied by Gambang Semarang music which combines Javanese music instruments, gamelan, and Chinese music instruments. In some occasions, songs such as Gambang Semarang and Gado-Gado Semarang are presented along with the music. Gambang Semarang dance itself is often considered as Semarang’s identity as the dance tries to embrace the multicultural society of Semarang which are Javanese, Chinese, and Arabs through the dance movements and the costume worn by the dancer. Data were collected through interviews with key informants. The results of the interviews then were analyzed to find out the stories represented by Gambang Semarang. The findings show that dance movements and costumes of Gambang Semarang indeed represent multicultural Semarang.

Design and simulation of a mobile robot, for the inspection of electrical lines

A mobile robot was designed and simulated for the inspection of electrical lines, which seeks to investigate alternatives that have the main necessary characteristics to perform these inspection tasks and implement them in a robot of accessible costs. In the robot design was modeled its mechanical parts in 3D and then previously taken to a virtual simulation software (Vrep), in which the sequence of movements were programmed, to pass obstacles.

Functional Role of Internal and External Visual Imagery: Preliminary Evidences from Pilates

The present study investigates whether a functional difference between the visualization of a sequence of movements in the perspective of the first- (internal VMI-I) or third- (external VMI-E) person exists, which might be relevant to promote learning. By using a mental chronometry experimental paradigm, we have compared the time or execution, imagination in the VMI-I perspective, and imagination in the VMI-E perspective of two kinds of Pilates exercises. The analysis was carried out in individuals with different levels of competence (expert, novice, and no-practice individuals). Our results showed that in the Expert group, in the VMI-I perspective, the imagination time was similar to the execution time, while in the VMI-E perspective, the imagination time was significantly lower than the execution time. An opposite pattern was found in the Novice group, in which the time of imagination was similar to that of execution only in the VMI-E perspective, while in the VMI-I perspective, the time of imagination was significantly lower than the time of execution. In the control group, the times of both modalities of imagination were significantly lower than the execution time for each exercise. The present data suggest that, while the VMI-I serves to train an already internalised gesture, the VMI-E perspective could be useful to learn, and then improve, the recently acquired sequence of movements. Moreover, visual imagery is not useful for individuals that lack a specific motor experience. The present data offer new insights in the application of mental training techniques, especially in field of sports. However, further investigations are needed to better understand the functional role of internal and external visual imagery.