scholarly journals Motor cost affects the decision of when to shift gaze for guiding movement

2019 ◽  
Vol 122 (1) ◽  
pp. 378-388 ◽  
Author(s):  
F. Javier Domínguez-Zamora ◽  
Daniel S. Marigold
Keyword(s):  
Center Of Mass ◽  
Relevant Information ◽  
Lateral Direction ◽  
Foot Placement ◽  
Factors Affecting ◽  
Direct Gaze ◽  
Trial Basis ◽  
Motor Actions ◽  
The Cost ◽  
The Brain

Frequent gait modifications are often required to navigate our world. These can involve long or wide steps or changes in direction. People generally prefer to minimize the motor cost (or effort) of a movement, although with changes in gait this is not always possible. The decision of when and where to shift gaze is critical for controlling motor actions, since vision informs the brain about the available choices for movement—in this case, where to step. Here we asked how motor cost influences the allocation of gaze. To address this, we had participants walk and step to the center of sequential targets on the ground. We manipulated the motor cost associated with controlling foot placement by varying the location of one target in the lateral direction on a trial-to-trial basis within environments with different numbers of targets. Costlier steps caused a switch from a gaze strategy of planning future steps to one favoring visual feedback of the current foot placement when participants had to negotiate another target immediately after. Specifically, costlier steps delayed gaze shifts away from the manipulated target. We show that this relates to the cost of moving the leg and redirecting the body’s center of mass from target to target. Overall, our results suggest that temporal gaze decisions are affected by motor costs associated with step-to-step demands of the environment. Moreover, they provide insight into what affects the coordination between the eyes and feet for the control of stable and accurate foot placement while walking. NEW & NOTEWORTHY Changes in gait allow us to navigate our world. For instance, one may step long or wide to avoid a spilled drink. The brain can direct gaze to gather relevant information for making these types of motor decisions; however, the factors affecting gaze allocation in natural behaviors are poorly understood. We show how the motor cost associated with a step influences the decision of when to redirect gaze to ensure accurate foot placement while walking.

scholarly journals Factors Affecting the Rate of Fuel Consumption in Aircrafts

2021 ◽  
Vol 13 (14) ◽  
pp. 8066
Author(s):  
Thowayeb H. Hassan ◽  
Abu Elnasr E. Sobaih ◽  
Amany E. Salem
Keyword(s):  
Fuel Consumption ◽  
Positive Association ◽  
Pollutant Emissions ◽  
Aviation Industry ◽  
Factors Affecting ◽  
Fuel Flow ◽  
Homogeneity Of Variance ◽  
Strong Positive Association ◽  
Ground Distance ◽  
The Cost

The cost of fuel and its availability are among the most major concerns for aircrafts and the aviation industry overall. Environmental difficulties with chemical pollutant emissions emitted by aviation machines are also connected to fuel consumption. As a result, it is crucial to examine factors that affect the overall fuel usage and consumption in the airport-based aviation industry. Several variables were investigated related to the total fuel consumed, such as dry operating weight (DOW) (KG), zero-fuel weight (ZFW), take-off weight (TOW), air distance (AIR DIST) (KM), and ground distance (GDN DIST). Analysis of the correlation between total fuel consumed as well as the extra fuel and selected variables was conducted. The results showed that the most positively associated factors with the total used fuel were the air distance (r2 = 0.86, p < 0.01), ground distance (r2 = 0.78, p < 0.01), TOW (r2 = 0.68, p < 0.01), and flight time (r2 = 0.68, p < 0.01). There was also a strong positive association between the average fuel flow (FF) and actual TOW (r2 = 0.74, p < 0.01) as well as ZFW (r2 = 0.61, p < 0.01). The generalized linear model (GLM) was utilized to assess the predictions of total energy usage after evaluating important outliers, stability of the homogeneity of variance, and the normalization of the parameter estimation. The results of multiple linear regression revealed that the most significant predictors of the total consumed fuel were the actual ZFW (p < 0.01), actual TOW (p < 0.01), and actual average FF (p < 0.05). The results interestingly confirmed that wind speed has some consequences and effects on arrival fuel usage. The result reflects that thermal and hydrodynamic economies impact on the flying fuel economy. The research has various implications for both scholars and practitioners of aviation industry.

scholarly journals Decision-related feedback in visual cortex lacks spatial selectivity

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Katrina R. Quinn ◽  
Lenka Seillier ◽  
Daniel A. Butts ◽  
Hendrikje Nienborg
Keyword(s):  
Contextual Information ◽  
Relevant Information ◽  
Common Mechanism ◽  
Spatial Selectivity ◽  
Population Responses ◽  
Stimulus Choice ◽  
Visual Areas ◽  
Computational Work ◽  
Feature Based ◽  
The Brain

AbstractFeedback in the brain is thought to convey contextual information that underlies our flexibility to perform different tasks. Empirical and computational work on the visual system suggests this is achieved by targeting task-relevant neuronal subpopulations. We combine two tasks, each resulting in selective modulation by feedback, to test whether the feedback reflected the combination of both selectivities. We used visual feature-discrimination specified at one of two possible locations and uncoupled the decision formation from motor plans to report it, while recording in macaque mid-level visual areas. Here we show that although the behavior is spatially selective, using only task-relevant information, modulation by decision-related feedback is spatially unselective. Population responses reveal similar stimulus-choice alignments irrespective of stimulus relevance. The results suggest a common mechanism across tasks, independent of the spatial selectivity these tasks demand. This may reflect biological constraints and facilitate generalization across tasks. Our findings also support a previously hypothesized link between feature-based attention and decision-related activity.

scholarly journals Economic burden of childhood diarrhea in Burundi

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Fulgence Niyibitegeka ◽  
Arthorn Riewpaiboon ◽  
Sitaporn Youngkong ◽  
Montarat Thavorncharoensap
Keyword(s):  
Economic Burden ◽  
Cost Model ◽  
Primary Treatment ◽  
Management Program ◽  
Community Based ◽  
Factors Affecting ◽  
Hospitalization Costs ◽  
Illness Study ◽  
The Cost ◽  
Substantial Economic Burden

Abstract Background In 2016, diarrhea killed around 7 children aged under 5 years per 1000 live births in Burundi. The objective of this study was to estimate the economic burden associated with diarrhea in Burundi and to examine factors affecting the cost to provide economic evidence useful for the policymaking about clinical management of diarrhea. Methods The study was designed as a prospective cost-of-illness study using an incidence-based approach from the societal perspective. The study included patients aged under 5 years with acute non-bloody diarrhea who visited Buyenzi health center and Prince Regent Charles hospital from November to December 2019. Data were collected through interviews with patients’ caregivers and review of patients’ medical and financial records. Multiple linear regression was performed to identify factors affecting cost, and a cost model was used to generate predictions of various clinical and care management costs. All costs were converted into international dollars for the year 2019. Results One hundred thirty-eight patients with an average age of 14.45 months were included in this study. Twenty-one percent of the total patients included were admitted. The average total cost per episode of diarrhea was Int$109.01. Outpatient visit and hospitalization costs per episode of diarrhea were Int$59.87 and Int$292, respectively. The costs were significantly affected by the health facility type, patient type, health insurance scheme, complications with dehydration, and duration of the episode before consultation. Our model indicates that the prevention of one case of dehydration results in savings of Int$16.81, accounting for approximately 11 times of the primary treatment cost of one case of diarrhea in the community-based management program for diarrhea in Burundi. Conclusion Diarrhea is associated with a substantial economic burden to society. Evidence from this study provides useful information to support health interventions aimed at prevention of diarrhea and dehydration related to diarrhea in Burundi. Appropriate and timely care provided to patients with diarrhea in their communities and primary health centers can significantly reduce the economic burden of diarrhea. Implementing a health policy to provide inexpensive treatment to prevent dehydration can save significant amount of health expenditure.

Factors affecting the future of the Scottish hydrometric network

1987 ◽  
Vol 78 (4) ◽  
pp. 269-274 ◽  
Author(s):  
T. Poodle
Keyword(s):  
Data Acquisition ◽  
Computer Systems ◽  
Economic Recession ◽  
Data Standards ◽  
Factors Affecting ◽  
Economic Climate ◽  
A Minor ◽  
The Cost ◽  
Minor Extent

ABSTRACTThe Scottish Hydrometric Network consists of a number of river gauging stations which have been located at sites considered suitable to provide long term flow records. Economic recession has placed some stress on the gauging programme, and has given rise to extensive closures of gauging stations in England and, to a minor extent so far, in Scotland. The way in which the network became established provides a mixture of strengths and weaknesses which could have unpredictable consequences in an adverse economic climate. Changing technology provides some opportunity to reduce the cost of data acquisition and improve the deployment of manpower, while maintaining data standards. In these changing circumstances, particularly with extensive use of computer systems, it is important that standards are established for data returned to the Water Archive and that the network is not allowed to degenerate by default.

Mechanical Analysis of Warm Extrusion Precision Forming on 42CrMo Steel Cutting Pick

2012 ◽  
Vol 538-541 ◽  
pp. 1061-1066 ◽  
Author(s):  
Chun Jian Su ◽  
Quan Lan Li ◽  
Lin Jing Xiao ◽  
Su Min Guo
Keyword(s):  
New Technology ◽  
Mechanical Analysis ◽  
Extrusion Force ◽  
Factors Affecting ◽  
42Crmo Steel ◽  
Pick Body ◽  
Mining Tool ◽  
Main Factors ◽  
The Cost ◽  
Warm Extrusion

Cutting pick is a kind of widely-used consumptive mining tool. The traditional producing technics of cutting pick body is foundry, or machining after roughly forging, or machining directly from metal bar. By former technics, the property of products is poor, and by latter, the material availability is low and the cost is high. The patent technology for cutting pick body warm extrusion introduced in this paper can overcome all the disadvantages mentioned above. In this paper, by analyzing the characteristic of cutting pick body warm extrusion, adopting the principle of power balance to solve the approximate solution of strain forces, the approximate calculating formulas of extruding power are deduced. The main factors affecting on extrusion force are determined theoretically. This research can be used as basis to design tooling and choose proper equipment for this new technology.

scholarly journals Perceptual decisions are biased toward relevant prior choices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Helen Feigin ◽  
Shira Baror ◽  
Moshe Bar ◽  
Adam Zaidel
Keyword(s):  
Sensory Information ◽  
Irrelevant Stimulus ◽  
Stimulus Feature ◽  
Serial Dependence ◽  
Low Level ◽  
Subsequent Test ◽  
Key Factor ◽  
High Level ◽  
Motor Actions ◽  
The Brain

AbstractPerceptual decisions are biased by recent perceptual history—a phenomenon termed 'serial dependence.' Here, we investigated what aspects of perceptual decisions lead to serial dependence, and disambiguated the influences of low-level sensory information, prior choices and motor actions. Participants discriminated whether a brief visual stimulus lay to left/right of the screen center. Following a series of biased ‘prior’ location discriminations, subsequent ‘test’ location discriminations were biased toward the prior choices, even when these were reported via different motor actions (using different keys), and when the prior and test stimuli differed in color. By contrast, prior discriminations about an irrelevant stimulus feature (color) did not substantially influence subsequent location discriminations, even though these were reported via the same motor actions. Additionally, when color (not location) was discriminated, a bias in prior stimulus locations no longer influenced subsequent location discriminations. Although low-level stimuli and motor actions did not trigger serial-dependence on their own, similarity of these features across discriminations boosted the effect. These findings suggest that relevance across perceptual decisions is a key factor for serial dependence. Accordingly, serial dependence likely reflects a high-level mechanism by which the brain predicts and interprets new incoming sensory information in accordance with relevant prior choices.

scholarly journals Development of a New KPI for the Economic Quantification of Six Big Losses and Its Implementation in a Cyber Physical System

2020 ◽  
Vol 10 (24) ◽  
pp. 9154
Author(s):  
Paula Morella ◽  
María Pilar Lambán ◽  
Jesús Royo ◽  
Juan Carlos Sánchez ◽  
Jaime Latapia
Keyword(s):  
Real Time ◽  
Physical System ◽  
Performance Indicator ◽  
Cost Model ◽  
Relevant Information ◽  
Cyber Physical System ◽  
Time Data ◽  
Real Time Data ◽  
Different Dimensions ◽  
The Cost

The purpose of this work is to develop a new Key Performance Indicator (KPI) that can quantify the cost of Six Big Losses developed by Nakajima and implements it in a Cyber Physical System (CPS), achieving a real-time monitorization of the KPI. This paper follows the methodology explained below. A cost model has been used to accurately develop this indicator together with the Six Big Losses description. At the same time, the machine tool has been integrated into a CPS, enhancing the real-time data acquisition, using the Industry 4.0 technologies. Once the KPI has been defined, we have developed the software that can turn these real-time data into relevant information (using Python) through the calculation of our indicator. Finally, we have carried out a case of study showing our new KPI results and comparing them to other indicators related with the Six Big Losses but in different dimensions. As a result, our research quantifies economically the Six Big Losses, enhances the detection of the bigger ones to improve them, and enlightens the importance of paying attention to different dimensions, mainly, the productive, sustainable, and economic at the same time.

ON THE INJURIOUS EFFECT OF THE BABY CARRIAGE ON THE PHYSICAL DEVELOPMENT OF THE YOUNG (1880)

PEDIATRICS ◽  
1982 ◽  
Vol 70 (6) ◽  
pp. 857-857
Author(s):  
T. E. C.
Keyword(s):  
Spinal Cord ◽  
General Rule ◽  
Physical Development ◽  
Medical Society ◽  
County Medical Society ◽  
Injurious Effect ◽  
The Cost ◽  
Brain And Spinal Cord ◽  
The Brain

On November 10, 1880, Dr. Henry H. Smith of Philadelphia read a paper before the Philadelphia County Medical Society in which he condemned the use of the baby carriage as follows: The advocates of the use of baby-carriages contend that they are beneficial by keeping an infant longer in the fresh air than can be done when it is carried by a nurse, who soon becomes fatigued. This is certainly not true in many instances, as a woman who is not strong enough to carry an infant, even if it weighs twenty-five pounds, is physically unfitted for her duty as a nurse. Such an objection is very apt to be raised by the nurses themselves, and should be regarded with suspicion by the mother. Often it is evidence of laziness or a fondness for flirtation or talking, as may be noted at any time in our parks or squares, and especially in Rittenhouse Square, where many nurses of wealthy children can be daily seen amusing themselves by the hour, totally regardless of the infant, who may be likewise seen with its head hanging out over the side of the carriage, so as to compress the veins of the neck and induce a certain degree of congestion of the brain, if it is not found in some equally-improper and injurious attitude likely to result in curvature or caries of the spine, the origin or exciting cause of which it is subsequently difficult to recognize. Another evil liable to ensue from the constant use of the baby-carriage is the jarring and concussion of the delicate brain and spinal cord of the infant, created by bouncing the carriage over gutters or up and down the curbstones of our sidewalks.... The baby-carriage mania has now reached that point in Philadelphia that an infant and a coach appear to be inseparable, and, though the cost of a baby-carriage is quite an item in the expenses of the nursery, "few there are so poor as not to do it reverence." Of course, it is admitted that there may be instances where the use of a baby-carriage occasionally by a child able to walk a little, or where the carriage permits a poor, tired mother to obtain for herself a little relaxation whilst keeping her baby in its carriage in the Park, or in the case of feeble children or those recuperating from an attack of illness, is advantageous: but, as a general rule, the anatomical and physiological facts just alluded to may be deemed as sufficient to induce physicians to give attention to the abuse of a custom that is by no means the result of necessity in the case of infants or those under twelve months of age.

A Qualitative Analysis of Factors Affecting the Successful Completion of Postgraduate Studies

2021 ◽  
Vol 12 (3) ◽  
pp. 152-161
Author(s):  
Abdul Munir Ismail Et.al
Keyword(s):  
Interpersonal Relationships ◽  
Relevant Information ◽  
Learning Approaches ◽  
Successful Completion ◽  
Structured Interviews ◽  
Postgraduate Students ◽  
Factors Affecting ◽  
Face To Face ◽  
Postgraduate Studies ◽  
Research Findings

The study aims to highlight the current learning approaches used by postgraduate students to complete their postgraduate studies on time, as studies have shown many students have failed to finish their studies as planned. In particular, this study focuses on factors and methods that are perceived to be most effective by students to help them complete their studies on time.  Methodology: Thisstudy was based on a qualitative approach involving semi-structured interviews. The study sample consisted of 14 postgraduate students and one lecturers as respondents. The research instrument was based on interview questions to elicit relevant information on their demography and learning practices. Data were collected and organized into four themes and were subsequently analyzed descriptively.     Findings: The findings showed that face-to-face discussions were the most popular practice adopted by the respondents. The findings also showed several factors had significant impacts on student learning, such as interpersonal relationships between students and supervisors, commitment, financial commitment, and moral support, which needs to be taken into account in helping students to complete on time.     Significance: The research findings can inform all the stakeholders, notably students, supervisors, and administrative officers, factors that have profound impacts on postgraduate students’ efforts to graduate on time.

Self-Controlled Practice Within a Fixed Time Period Facilitates the Learning of a Basketball Set Shot

2014 ◽  
Vol 2 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Phillip G. Post ◽  
Jeffrey T. Fairbrother ◽  
Joao A. C. Barros ◽  
J. D. Kulpa
Keyword(s):  
Motor Learning ◽  
Instructional Support ◽  
Fixed Time ◽  
Relevant Information ◽  
Self Control ◽  
Time Period ◽  
Trial Basis ◽  
Practice Trials ◽  
Additional Support ◽  
Do So

Allowing self-control over various modes of instructional support has been shown to facilitate motor learning. Most research has examined factors that directly altered task-relevant information on a trial-to-trial basis (e.g., feedback). Recent research suggests that self-control (SC) effects extend to the manipulation of other types of factors (e.g., total number of practice trials completed). This research also illustrated that learners sometimes select a very small amount of practice when given latitude to do so. The purpose of the current study was to examine the effects of SC practice within a fixed time period on the learning of a basketball set shot. SC participants chose when to attempt each shot within two 15-min practice sessions, thereby controlling both the total number of shots taken and the spacing of shots. Yoked participants completed the same number of shots as their SC counterparts. Spacing of shots was also matched across groups. The SC group was more accurate and had higher form scores and longer preshot times during retention. These findings provided additional support for the generalizability of SC effects and extended prior research, showing that autonomy over total practice duration was not a prerequisite for the observed effects.

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