scholarly journals Water striders adjust leg movement speed to optimize takeoff velocity for their morphology

2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Eunjin Yang ◽  
Jae Hak Son ◽  
Sang-im Lee ◽  
Piotr G. Jablonski ◽  
Ho-Young Kim
2016 ◽  
Vol 1 (15) ◽  
pp. 79-83
Author(s):  
Ed Bice ◽  
Kristine E. Galek

Dysphagia is common in patients with dementia. Dysphagia occurs as a result of changes in the sensory and motor function of the swallow (Easterling, 2007). It is known that the central nervous system can undergo experience-dependent plasticity, even in those individuals with dementia (Park & Bischof, 2013). The purpose of this study was to explore whether or not the use of neuroplastic principles would improve the swallow motor plan and produce positive outcomes of a patient in severe cognitive decline. The disordered swallow motor plan was manipulated by focusing on a neuroplastic principles of frequency (repetition), velocity of movement (speed of presentation), reversibility (Use it or Lose it), specificity and adaptation, intensity (bolus size), and salience (Crary & Carnaby-Mann, 2008). After five therapeutic sessions, the patient progressed from holding solids in her mouth with decreased swallow initiation to independently consuming a regular diet with full range of liquids with no oral retention and no verbal cues.


2020 ◽  
Vol 15 (2) ◽  
pp. 63-73
Author(s):  
Young-Joo Moon ◽  
Won-Bin Shin ◽  
Gwang-Hyun Ryu ◽  
Ji-Yun Lee ◽  
Hyun-A Jeon ◽  
...  

2021 ◽  
pp. 1-11
Author(s):  
Sang-Ki Jeong ◽  
Dea-Hyeong Ji ◽  
Ji-Youn Oh ◽  
Jung-Min Seo ◽  
Hyeung-Sik Choi

In this study, to effectively control small unmanned surface vehicles (USVs) for marine research, characteristics of ocean current were learned using the long short-term memory (LSTM) model algorithm of a recurrent neural network (RNN), and ocean currents were predicted. Using the results, a study on the control of USVs was conducted. A control system model of a small USV equipped with two rear thrusters and a front thruster arranged horizontally was designed. The system was also designed to determine the output of the controller by predicting the speed of the following currents and utilizing this data as a system disturbance by learning data from ocean currents using the LSTM algorithm of a RNN. To measure ocean currents on the sea when a small USV moves, the speed and direction of the ship’s movement were measured using speed, azimuth, and location (latitude and longitude) data from GPS. In addition, the movement speed of the fluid with flow velocity is measured using the installed flow velocity measurement sensor. Additionally, a control system was designed to control the movement of the USV using an artificial neural network-PID (ANN-PID) controller [12]. The ANN-PID controller can manage disturbances by adjusting the control gain. Based on these studies, the control results were analyzed, and the control algorithm was verified through a simulation of the applied control system [8, 9].


2020 ◽  
pp. 1-12
Author(s):  
Linuo Wang

The current technology related to athlete gait recognition has shortcomings such as complicated equipment and high cost, and there are also certain problems in recognition accuracy and recognition efficiency. In order to improve the efficiency of athletes’ gait recognition, this paper studies the different recognition technologies of athletes based on machine learning and spectral feature technology and applies computer vision technology to sports. Moreover, according to the calf angular velocity signal, the occurrence of leg movement is detected in real time, and the gait cycle is accurately divided to reduce the influence of the signal unrelated to the behavior on the recognition process. In addition, this study proposes a gait behavior recognition method based on event-driven strategies. This method uses a gyroscope as the main sensor and uses a wearable sensor node to collect the angular velocity signals of the legs and waist. In addition, this study analyzes the performance of the algorithm proposed by this paper through experimental research. The comparison results show that the method proposed by this paper has improved the number of recognition action types and accuracy and has certain advantages from the perspective of computation and scalability.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 524.3-525
Author(s):  
M. Patanè ◽  
L. Carmisciano ◽  
E. Hysa ◽  
E. Gotelli ◽  
A. Signori ◽  
...  

Background:Rheumatoid arthritis (RA) is a long-term, progressive, and disabling autoimmune disease1. The disease activity can be quantified by the Disease Activity Score 28-joint count – C reactive protein (DAS28crp)2; the evaluation of disability function (DF) is actually mainly performed only by subjective Patient Reported Outcomes (PROs) like Health Assessment Questionnaire (HAQ)3; to investigate the functional aspects of RA hands it is usually used the grip strength (GS)4. However, in the scientific literature no tool, which objectively evaluates movement speed, has been reported. The Hand Test System (HTS, ETT) is an engineered glove (RAGLOVE), nowadays applied for neuroscience studies to evaluate hand motility5Objectives:To objectively evaluate the RA hand’s speed of the fine movements, through the HTS and to compared with a group of age and sex matched healthy controls. To verify the correspondence with the HAQ, DAS28, GS.Methods:55 consecutives RA patients (pts) (6 males, age 61 ± 16 years, mean duration of disease 12 ± 8 years), classified according to 2010 ACR/EULAR criteria6, and 50 matched healthy controls (HCs) were enrolled. After consent, all participants undergone HTS test that recognizes the touches between the finger tips during the opposition movements of the hands in standard sequences of movements, after dressed the glove. A multiple finger evaluation (MFE) and a single finger evaluation (SFE) were performed using a dedicated software that provided the physician the following quantitative parameters: Touch Duration (TD), Inter Tapping Interval (ITI) and Movement Rate (MR). Average time for hand 2 minutes. RA pts compiled the HAQ, performed the GS and a DAS28cpr was performed.The student’s t-test was used to compare the glove’s parameters between the groups whereas the analysis of variance (ANOVA) was utilized to verify potential differences between the populations. In order to evaluate the single correlations, the r and p values of Pearson were employed.Results:For MFE, glove parameters TD and ITI were significantly higher in RA pts than HCs, whereas; MR was significantly lower in RA pts compared to HCs (all p <0.001).For SFE non-affected fingers (not swollen and not tender) of RA pts performed better than a clinically affected fingers, but in any case significantly worse than average HCs fingers (p < 0.001).There is a statistically significant correlation between the GS and MR (r= 0.39 p=0.003) and TD (r=-0.33 p=0.015).TD, ITI e MR of RA pts showed a significant correlation with the total score of the HAQ (r = 0.56, r = 0.39, r = -0.56, all p < 0.001;). DAS28, considered as a continuous variable, proved to be significantly correlated with the TD (r = 0.36, p = 0.009). When the RA patients were grouped according to the disease activity by DAS28cpr7, there was an increase of one third of the TD’s logarithm for each increase in the activity class (linear regression with ordinal predictors, beta = 0.33; 95%CI 0.03, 0.63,p < 0.0297). Finally, even RA pts in remission showed a TD significantly higher compared with HCs (p= 0.034).Conclusion:The RAGLOVE is shown as a new safe and fast tool to evaluate a new objective parameter in the hand’s functionality: the speed of finger movements. In RA pts, an inversely proportional correlation emerges between the speed of movement and disease activity.The significant correlation found with HAQ, highlights the loss of motility of the hands as one of the main determinant of disability. The RAGLOVE is now tested in RA patients undergoing treatment.References:[1]Hakkinen et al Ann Rheum Dis. 2005;[2]Van Der Heijde et al J of Rheum. 1993;[3]Fries et al Arthritis Rheum. 1980;[4]Mathiowetz et al J Hand Surg Am. 1984;[5]Carmisciano et al Eur J Neurol. 2020;[6]Aletaha et al. Ann Rheum Dis. 2010;[7]Aletaha et al Arthritis Rheum 2005.Disclosure of Interests:None declared


1932 ◽  
Vol 16 (2) ◽  
pp. 349-355 ◽  
Author(s):  
John H. Welsh

1. The speed of progression of Unionicola, a water mite, is influenced by light; and over a certain range increases as a function of the light intensity. 2. The relation between speed and light intensity is not a simple one, as the speed of progression is due to the combined effect of amplitude of steps and frequency of leg movement. 3. The amplitude of stride increases in direct proportion to the logarithm of the light intensity, while the frequency of stepping has no such simple relation to intensity. 4. The change in length of stride with changing light intensity indicates a tonic effect of light on the locomotor muscles. Such an effect has been observed previously in studies of orientation, due to unequal illumination, which produces changes in posture.


Sign in / Sign up

Export Citation Format

Share Document