movement strategies
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2021 ◽  
Author(s):  
Javier Corrales

The first section of this Element reviews the history of LGBTQ rights in the region since the 1960s. The second section reviews explanations for the expansion of rights and setbacks, especially since the mid 2000s. Explanations are organized according to three themes: (1) the (re-)emergence of a religious cleavage; (2) the role of political institutions such as presidential leadership, political parties, federalism, courts, and transnational forces; and (3) the role of social movement strategies, and especially, unity. The last section compares the progress on LGBTQ rights (significant) with reproductive rights (insignificant). This Element concludes with an overview of the causes and possible future direction of the current backlash against LGBTQ rights.


Sensors ◽  
2021 ◽  
Vol 21 (24) ◽  
pp. 8303
Author(s):  
Jia-Wen Yam ◽  
Jing-Wen Pan ◽  
Pui-Wah Kong

To better understand the biomechanics of para-table tennis players, this study compared the shoulder, elbow, and wrist joint kinematics among able-bodied (AB) and wheelchair players in different classifications. Nineteen participants (AB, n = 9; classification 1 (C1), n = 3; C2, n = 3; C3, n = 4) executed 10 forehand and backhand topspin drives. Shoulder abduction/adduction, elbow flexion/extension, wrist extension/flexion, respective range of motion (ROM), and joint patterns were obtained using inertial measurement unit (IMU) sensors. The results showed clear differences in upper limb kinematics between the able-bodied and wheelchair players, especially in the elbow and wrist. For the para-players, noticeable variations in techniques were also observed among the different disability classes. In conclusion, wheelchair players likely adopted distinct movement strategies compared to AB to compensate for their physical impairments and functional limitations. Hence, traditional table tennis programs targeting skills and techniques for able-bodied players are unsuitable for para-players. Future work can investigate how best to customize training programs and to optimize movement strategies for para-players with varied types and degrees of impairment.


Symmetry ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2388
Author(s):  
Mohammad H. Nadimi-Shahraki ◽  
Shokooh Taghian ◽  
Seyedali Mirjalili ◽  
Ahmed A. Ewees ◽  
Laith Abualigah ◽  
...  

The moth-flame optimization (MFO) algorithm is an effective nature-inspired algorithm based on the chemical effect of light on moths as an animal with bilateral symmetry. Although it is widely used to solve different optimization problems, its movement strategy affects the convergence and the balance between exploration and exploitation when dealing with complex problems. Since movement strategies significantly affect the performance of algorithms, the use of multi-search strategies can enhance their ability and effectiveness to solve different optimization problems. In this paper, we propose a multi-trial vector-based moth-flame optimization (MTV-MFO) algorithm. In the proposed algorithm, the MFO movement strategy is substituted by the multi-trial vector (MTV) approach to use a combination of different movement strategies, each of which is adjusted to accomplish a particular behavior. The proposed MTV-MFO algorithm uses three different search strategies to enhance the global search ability, maintain the balance between exploration and exploitation, and prevent the original MFO’s premature convergence during the optimization process. Furthermore, the MTV-MFO algorithm uses the knowledge of inferior moths preserved in two archives to prevent premature convergence and avoid local optima. The performance of the MTV-MFO algorithm was evaluated using 29 benchmark problems taken from the CEC 2018 competition on real parameter optimization. The gained results were compared with eight metaheuristic algorithms. The comparison of results shows that the MTV-MFO algorithm is able to provide competitive and superior results to the compared algorithms in terms of accuracy and convergence rate. Moreover, a statistical analysis of the MTV-MFO algorithm and other compared algorithms was conducted, and the effectiveness of our proposed algorithm was also demonstrated experimentally.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Elia Mercado-Palomino ◽  
Francisco Aragón-Royón ◽  
Jim Richards ◽  
José M. Benítez ◽  
Aurelio Ureña Espa

AbstractThe identification of movement strategies in situations that are as ecologically valid as possible is essential for the understanding of lower limb interactions. This study considered the kinetic and kinematic data for the hip, knee and ankle joints from 376 block jump-landings when moving in the dominant and non-dominant directions from fourteen senior national female volleyball players. Two Machine Learning methods were used to generate the models from the dataset, Random Forest and Artificial Neural Networks. In addition, decision trees were used to detect which variables were relevant to discern the limb movement strategies and to provide a meaningful prediction. The results showed statistically significant differences when comparing the movement strategies between limb role (accuracy > 88.0% and > 89.3%, respectively), and when moving in the different directions but performing the same role (accuracy > 92.3% and > 91.2%, respectively). This highlights the importance of considering limb dominance, limb role and direction of movement during block jump-landings in the identification of which biomechanical variables are the most influential in the movement strategies. Moreover, Machine Learning allows the exploration of how the joints of both limbs interact during sporting tasks, which could provide a greater understanding and identification of risky movements and preventative strategies. All these detailed and valuable descriptions could provide relevant information about how to improve the performance of the players and how to plan trainings in order to avoid an overload that could lead to risk of injury. This highlights that, there is a necessity to consider the learning models, in which the spike approach unilaterally is taught before the block approach (bilaterally). Therefore, we support the idea of teaching bilateral approach before learning the spike, in order to improve coordination and to avoid asymmetries between limbs.


2021 ◽  
Author(s):  
Aaron L Wong ◽  
Audrey L Green ◽  
Mitchell W Isaacs

When faced with multiple potential movement options, individuals either reach directly to one of the options, or initiate a reach intermediate between the options. It remains unclear why people generate these two types of behaviors. Using the go-before-you-know task (commonly used to study behavior under choice uncertainty), we examined two key questions. First, do these two types of responses reflect distinct movement strategies, or are they simply examples of a more general response to choice uncertainty? If the former, the relative desirability (i.e., weighing the likelihood of successfully hitting the target versus the attainable reward) of the two target options might be computed differently for direct versus intermediate reaches. We showed that indeed, when exogenous reward and success likelihood (i.e., endogenous reward) differ between the two options, direct reaches were more strongly biased by likelihood whereas intermediate movements were more strongly biased by reward. Second, what drives individual differences in how people respond under uncertainty? We found that risk/reward-seeking individuals generated a larger proportion of intermediate reaches and were more sensitive to trial-to-trial changes in reward, suggesting these movements reflect a strategy to maximize reward. In contrast, risk-adverse individuals tended to generate more direct reaches in an attempt to maximize success. Together, these findings suggest that when faced with choice uncertainty, individuals adopt movement strategies consistent with their risk/reward-seeking tendency, preferentially biasing behavior toward exogenous rewards or endogenous success and consequently modulating the relative desirability of the available options.


Author(s):  
Christoph Netz ◽  
Hanno Hildenbrandt ◽  
Franz J. Weissing

AbstractThe coevolution of predators and prey has been the subject of much empirical and theoretical research that produced intriguing insights into the interplay of ecology and evolution. To allow for mathematical analysis, models of predator–prey coevolution are often coarse-grained, focussing on population-level processes and largely neglecting individual-level behaviour. As selection is acting on individual-level properties, we here present a more mechanistic approach: an individual-based simulation model for the coevolution of predators and prey on a fine-grained resource landscape, where features relevant for ecology (like changes in local densities) and evolution (like differences in survival and reproduction) emerge naturally from interactions between individuals. Our focus is on predator–prey movement behaviour, and we present a new method for implementing evolving movement strategies in an efficient and intuitively appealing manner. Throughout their lifetime, predators and prey make repeated movement decisions on the basis of their movement strategies. Over the generations, the movement strategies evolve, as individuals that successfully survive and reproduce leave their strategy to more descendants. We show that the movement strategies in our model evolve rapidly, thereby inducing characteristic spatial patterns like spiral waves and static spots. Transitions between these patterns occur frequently, induced by antagonistic coevolution rather than by external events. Regularly, evolution leads to the emergence and stable coexistence of qualitatively different movement strategies within the same population. Although the strategy space of our model is continuous, we often observe the evolution of discrete movement types. We argue that rapid evolution, coexistent movement types, and phase shifts between different ecological regimes are not a peculiarity of our model but a result of more realistic assumptions on eco-evolutionary feedbacks and the number of evolutionary degrees of freedom.


Author(s):  
Pieter Severijns ◽  
Thomas Overbergh ◽  
Kaat Desloovere ◽  
Lieven Moke ◽  
Lennart Scheys

2021 ◽  
Vol 4 (3) ◽  
pp. 503-517
Author(s):  
Dyah Putri Fadillah ◽  
Istikomah Istikomah

The purpose of the study is to know how the implementation strategies in SDN Bubutan IV Surabaya. The descriptive qualitative method is used in this analysis. The collecting data technique is using data reduction, data display, and conclusion drawing. The data validity test is using source triangulation. The result of the study showed that the school literacy movement strategies are already successful with (1) conditioned physical environment with mini-libraries in each classroom and student artworks around school areas, (2) conditioned the social environment as an effective model by giving rewards toward students, there is also an activity to celebrate a national holiday that integrated with literacy learning, and (3) conditioned the academic environment with an accustomed student to read 15 minutes, the existence of school literacy team and having a library with proper facilities. 


2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Pengzhen Du ◽  
Ning Liu ◽  
Haofeng Zhang ◽  
Jianfeng Lu

The traveling salesman problem (TSP) is a typical combinatorial optimization problem, which is often applied to sensor placement, path planning, etc. In this paper, an improved ACO algorithm based on an adaptive heuristic factor (AHACO) is proposed to deal with the TSP. In the AHACO, three main improvements are proposed to improve the performance of the algorithm. First, the k-means algorithm is introduced to classify cities. The AHACO provides different movement strategies for different city classes, which improves the diversity of the population and improves the search ability of the algorithm. A modified 2-opt local optimizer is proposed to further tune the solution. Finally, a mechanism to jump out of the local optimum is introduced to avoid the stagnation of the algorithm. The proposed algorithm is tested in numerical experiments using 39 TSP instances, and results shows that the solution quality of the AHACO is 83.33% higher than that of the comparison algorithms on average. For large-scale TSP instances, the algorithm is also far better than the comparison algorithms.


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