Double Legs Research Articles

Contribution of Double Legs Speed Hops and Pull Down Resistance Bands Training to the 50 Meter Breaststroke Swimming Speed of Male K.U II Athletes at the Medan Aquatic Swimming Club in 2023

This research is an experimental study whose aim is to determine the contribution of Double Legs Speed Hops and Pull Down Resistance Bands training to the 50 Meter Breaststroke Swimming Speed of Male K.U II Athletes at the Medan Aquatic Swimming Club in 2023. The population of swimming athletes at the Aquatic Swimming Club totaling 20 people, using purposive sampling technique a sample of 8 people was obtained. The research was conducted for 6 weeks, 18 meetings and 3 times a week. Before testing the hypothesis, a prerequisite Normality test was carried out using the Lilifors test so that the three variables were normal and the Homogeneity test (F test) then the three variables after testing the data were homogeneous. Hypothesis analysis produces Fcount = 7.259 and Ftable = 5.79 so that Fcount > Ftable so after testing it can be concluded that there is a significant contribution from Double Legs Speed Hops and Pull Down Resistance Bands training to 50 Breaststroke Swimming Speed K.U II Male Athlete Meter at Aquatic Swimming Club Medan in 2023.

Seismic performance of coupled shear walls with novel hybrid construction methods under high axial loading

In this paper, two novel hybrid construction methods were proposed for coupled beam shear walls with both prefabricated and cast-in-place (CIP) components in order to control the construction quality, reduce environmental impact and accelerate the construction speed for high-rise buildings. The first one was designated as a composite wall, which consisted of an inner prefabricated frame wall and an outer post-cast frame wall. The second one was a post-cast beam coupled wall, which was made of double prefabricated wall legs and a CIP coupling beam. A full-scale experiment was then designed to test five specimens of identical geometrical dimensions and structural details under a constant high axial load ratio of 0.5 and cyclic loads to evaluate the seismic performance. They were one CIP, two identical composite walls, and two identical post-cast beam coupled walls. The results indicate that: (1) the proposed hybrid prefabricated shear walls had almost similar flexural failure modes and cracking distribution with the CIP wall; (2) both proposed walls had comparable seismic performance with the CIP wall in terms of lateral load capacity, deformability and ductility; (3) the proposed composite walls had significantly larger energy dissipation capacity than the CIP wall; (4) the identical walls of the same construction method had similar performance, indicating a stable performance of the proposed walls; (5) under the high axial loading, the ductility of the proposed walls had a good ductility in the range of 3.25–3.83. Overall, the proposed walls have a satisfactory seismic performance and hence can be taken as an alternative for the conventional CIP coupled shear walls in practice for high-rise buildings.

Modeling and invariably horizontal control for the parallel mobile rescue robot based on PSO-CPG algorithm

AbstractA walking robot consisting of double Stewarts parallel legs was designed by our research team in the past time, which was mainly used for the transportation of the wounded after the disaster. In order to promote stability of control locomotion and ensure invariably horizontal state of the robot platform in the process of motion, the central pattern generator (CPG) based on particle swarm optimization (PSO) is presented to optimize the kinematic model. The purpose of optimization is to solve the hysteresis problem of displacement variation among the electric cylinders. Moreover, the dynamic model of the robot is established, which can provide mechanical basis for the feedback of control signal and make the robot move stably. The simulation results show that the displacement hysteresis problem of the electric cylinders is solved well. Meanwhile, compared with simulation results based on GA-CPG method, it is demonstrated that the robot motion planned using PSO-CPG method has better motion stability and can avoid the impact of legs landing during the transition phase of the motion cycle. The experimental results show that the platform on the robot can maintain an invariably horizontal state, and the locomotion is more stable. It verifies the feasibility of PSO-CPG model and the correctness of the dynamic model of the parallel mobile rescue robot.

Single-textured insole for the less affected leg in freezing of gait: A hypothesis.

Freezing of gait (FoG) is one of the most widely distributed and disabling gait phenomena in people with Parkinson's disease (PD). The current therapeutic interventions show suboptimal efficacy in FoG. Lower extremity proprioception impairments, especially in the most affected leg, gait initiation hesitation, and gait asymmetry are FoG factors, and there is a need to accurately consider them in terms of therapeutic approaches. Accordingly, we hypothesize that using a single-textured insole for the less affected leg may improve FoG by providing proprioceptive stimulation that enhances sensory processing and reduces gait hesitation and asymmetry. Proprioceptive sensory stimulation for the less affected limb could be more effective than for the double legs that are currently used in rehabilitation settings due to the sensory processing in the less affected basal ganglia being better.

Development of an Imaging Evaluation System for Low Back Pain

PurposeTo design a low back pain (LBP) imaging evaluation system for non-professional operators, quantifying risk of LBP in patients and asymptomatic individuals.MethodsTwenty-one previously asymptomatic subjects and five LBP patients diagnosed by a physician performed a series of test movements under a fixed camera, including hip abduction test, forward bending test, side bending test, double legs lowering test (DLLT), and modified Thomas test. The video clips were analyzed by a system program interface and were classified into a score from 1 to 4. The average total scores of the two groups were compared. Five intact subjects were retested to verify reliability. Twelve intact subjects and three patients’ clips were viewed by an experienced therapist to verify system validity.ResultsThe average total scores of two groups were significantly different (p = 0.0004). The results of hip abduction test, forward bending test, side bending test and DLLT showed significant differences between the two groups. The total score of two trials in the retest experiment exhibited a similar result (p = 0.058), with good linear correlation (r = 0.98). The total scores of the evaluations by the experienced therapist and the system program interface agreed with each other (p = 0.141; linear correlation r = 0.90).ConclusionThe evaluation system showed potential utility in screening LBP risk, with acceptable test–retest reliability and expert validity.

Experimental study on flow distribution and mixing at the core inlet of double-loop small module reactor

In this paper, an experiment is conducted on a 1/3 scaled-down hydraulic model of SMR to study the flow distribution and mixing characteristics of the reactor, in which the double cold legs and double hot legs are arranged symmetrically. The flow distribution factors and mixing coefficients are obtained by measuring the flow rates and conductivities at the inlet of each fuel assembly simulators, respectively. Especially, the velocity effect on flow distribution and mixing are also analyzed. Results indicate that the flow rate is higher in the central area, and the mixing coefficient decreases with the distance from the injected cold leg. By comparison, the velocity has a slight effect on the flow distribution and mixing, since the turbulent flow is fully developed and has entered self-similar region. Based on this work, the essential data for the structure design, thermal–hydraulic and safety analysis of the SMR are gained.

Comparison of MRI cross-sectional area and functions of core muscles among asymptomatic individuals with and without lumbar intervertebral disc degeneration

BackgroundPrevious studies suggested that patients with symptomatic intervertebral disc degeneration (IDD) of lumbar spine have reduced cross-sectional area (CSA) and functions of core muscles. However, reduced CSA and functions of core muscles have been observed not only in patients with symptomatic IDD but also in patients with other subgroups of low back pain (LBP). Thus, it is uncertain whether reduced CSA and functions of core muscles lead to IDD and LBP, or pain leads to reduced CSA and functions of core muscles in patients with symptomatic IDD. Therefore, this study aimed to compare the CSA and functions of core muscles between asymptomatic participants with and without IDD in magnetic resonance imaging (MRI).MethodsTwenty asymptomatic participants (12 men and 8 women) participated in this study. Ten participants had asymptomatic IDD at L4–5. The others were healthy controls (without IDD at all levels of lumbar spine). The CSA of core muscles was measured using MRI. Maximal isometric trunk flexor strength and side bridge strength were measured by a Smart KEMA strength sensor. Trunk flexor endurance test, side bridge endurance test and plank endurance test were used to measure core endurance. Double legs loading test was used to measure core stability. Mann-Whitney U test was used to compare the differences between two groups.ResultsThere were no significant differences in core muscle functions between the two groups (p > 0.05). Moreover, there was no significant difference in CSA between the two groups (p > 0.05).ConclusionsThere was no significant difference in CSA and core muscle functions between asymptomatic participants with and without IDD. These findings indicate that a degenerative or bulging disc in asymptomatic individuals has little effect on CSA and functions of core muscles, especially in young age. Therefore, the general core endurance test or strength test could not differentiate asymptomatic people with and without IDD of lumbar spine.Trial registration numberClinical Research information Service. KCT0004061. Registered 13 June 2019. retrospectively registered.

Changes in Lower-Limb Biomechanics, Soft Tissue Vibrations, and Muscle Activation During Unanticipated Bipedal Landings.

We aimed to explore the biomechanical differences between the anticipated drop jump and unanticipated drop landing. Twelve male collegiate basketball players completed an anticipated drop jump and unanticipated drop landing with double legs from a height of 30 cm. Kinematics, impact force, soft tissue vibrations, and electromyographic (EMG) amplitudes of the dominant leg were collected simultaneously. The anticipated drop jump showed more flexed lower limbs during landing and increased range of motion compared to the unanticipated drop landing. The anticipated drop jump also had lower impact force, lesser soft tissue vibration, and a greater damp coefficient at the thigh muscles compared with the unanticipated drop landing. Significant increases in the EMG amplitudes of the tibialis anterior, lateral gastrocnemius, rectus femoris, and biceps femoris were observed in the anticipated drop jump during the pre/post-activation and downward phases. The anticipated drop jump presented more optimized landing posture control with more joint flexion, lower impact force, less soft tissue vibrations, and full preparation of muscle activations compared with the unanticipated drop landing.

THE POST ACTIVATION POTENTIATION EFFECT OF TWO DIFFERENT CONDITIONING STIMULI ON DROP JUMP PARAMETERS ON YOUNG FEMALE ARTISTIC GYMNASTS

The purpose of this study was to examine the post activation potentiation (PAP) effect of two different conditioning stimuli (CS) on drop jump (DJ) parameters on young female gymnasts. Thirty young female artistic gymnasts, aged 8 to 13 years old performed two protocols of either double tuck jumps (DTJ: 2 sets of 5 repetitions) or legs blocking action (LBA: 2 sets of 5 repetitions) in a within-subject randomized design. Before and immediately after the PAP treatment and 4, 8, 12, and 16 min after, jumping ability was measured by performing a drop jump (DJ). Statistical analysis revealed significant interaction effect between the two CS for DJ height (p < 0.002), time flight (p < 0.002) and take-off velocity (p < 0.003). Furthermore, significant main effect was found for protocol on DJ height (p < 0.001) and time flight (p < 0.001). It is recommended to the sports experts to include similar condition stimuli in the warm-up procedure, in order to improve their jumping performance. Conclusive both CS cause PAP phenomenon but the specialized CS produces higher rates of improvements in young female artistic gymnasts.

The Belt and Road Initiative and China’s Grand Diplomacy

On March 28, 2015, Chinese President Xi Jinping detailed his vision for the Silk Road Economic Belt and the 21st Century Maritime Silk Road (hereinafter referred to as the Belt and Road) when attending the Boao Forum for Asia. After this, China’s National Development and Reform Commission, Ministry of Foreign Affairs, and Ministry of Commerce jointly issued the “Vision and Actions on Jointly Building Silk Road Economic Belt and 21st Century Maritime Silk Road”, a sign that the Belt and Road Initiative promoted by China as a foreign cooperation platform entered its first year of implementation. This vision covers over half of the global population and involves more than 60 countries along the routes, the economic aggregates of which account for about one-third of the world. During 2015, Chinese President Xi Jinping and Premier Li Keqiang paid frequent visits to all continents in an effort to promote the implementation of the Belt and Road Initiative. At present, the Belt and Road Initiative has received positive responses from the countries along the routes, and a number of cooperation projects have been underway smoothly. With the implementation of the Belt and Road Initiative, China is forming a grand diplomatic landscape with “double legs” (a new type of major power relations and the Belt and Road Initiative) and a “single circle” (peripheral diplomacy). The Belt and Road Initiative highlights the spirit of the age, characterized by “peace, mutual respect, openness, and inclusiveness”, and has major international significance in helping China break through the security dilemma among nations, shoulder the responsibilities of a great power, and build China’s soft power in the international arena.

Comparison of Cardiorespiratory function between Single and Double Legs Rope Jumping Exercise

PURPOSE: To investigate differences in cardiorespiratory function between single leg (SL) and double legs (DL) rope jump. METHODS: Nine healthy males, age ranged between 19 and 21 years, (Meanage = 20.22 ± 0.66 yr, Meanweight = 65.11 ± 9.19 kg, Meanheight = 174.22 ± 4.38 cm, Mean BMI = 22.26 ± 3.14 kg/m2 and Mean RHR = 68.44 ± 10.32 beat/min respectively). All participants were performed jump rope exercises either a SL or DL jump conditions at the intensity of 72 skips per min for 5 minutes. The order of each jump rope condition was randomly assigned. Participants were allowed to have a 15-min rest between each condition. Prior to the testing, anthropometric data including body weight (BW), height, BMI resting heart rate (RHR) were collected. Cardiorespiratory function measurement volume of oxygen consumption (VO2) and volume of carbondioxide (VCO2) were collected during exercises. Dependent t-tests were employed to determine differences between the two conditions. RESULTS: SL had no significantly lower VO2 during exercise (1,595.87 ± 230.06 ml/min) as compared to DL (1,670.70±278.87 ml/min) (p = 0.473). The VO2/BW of SL (24.58 ± 2.69 ml/min/kg) was no statistically lower than DL (25.90 ± 4.43 ml/min/kg) (p = 0.396). No statistical significant differences were found, the VCO2 of DL (1,738.00 ± 454.60 ml/min) was higher than SL (1,717.38 ± 223.93 ml/min) (p = 0.890). CONCLUSIONS: There was no difference in cardiorespiratory function between rope jumping styles in 5 min.

Comparison of Oxygen Uptake between Single and Double Legs Rope Jumping Exercise

PURPOSE: To investigate differences in oxygen uptake (VO2) between single leg (SL) and double legs (DL) rope jump. METHODS: Nine healthy males, age ranged between 19 and 21 years, (Meanage, Meanweight and Meanheight of 20.22 ± 0.66 yr, 65.11 ± 9.19 kg and 174.22 ± 4.38 cm, respectively). All participants were performed jump rope exercises either a SL or DL jump conditions at the intensity of 72 round/min for 5 minutes. The order of each jump rope condition was randomly assigned. Participants were allowed to have a 15-min rest between each condition. Prior to the testing, anthropometric data including body weight (BW), height, BMI resting heart rate (RHR) were collected. Cardiorespiratory fitness measurement volume of carbondioxide (VCO2) and volume of oxygen uptake (VO2) were collected during exercises. Dependent t-tests were employed to determine differences between the two conditions. RESULTS: SL had lower VO2 (1,970.22 ± 304.12 ml/min) as compared to DL (2,150.78±403.69 ml/min) (p = 0.003). The VO2/BW of SL (30.28 ± 2.75 ml/min/kg) was also lower than DL (33.02 ± 4.65ml/min/kg) (p = 0.021). Although no statistical significant differences were found, the VCO2 of DL (2,453.33 ± 584.18 ml/min) was higher than SL (2,199.44 ± 314.19 ml/min) (p = 0.073). CONCLUSIONS: Oxygen uptake of DL rope jump had higher than SL rope jump in 5 min.

Control Algorithm for Inner Skeleton Frame Type Biped Walking Robot.

We developed inner skeleton type biped walking robot to work as cooperating with a human being and instead of a human being. Force sensors installed in the actuator of ISR-1 measure the outside forces, which realizes the relaxation motion similarly to muscle of a human being. This system is composed of the easy mechanisms. When a relaxation motion works, there are characteristics that a restraint problem on the angle of the joint in double legs supporting phase is dissolved. This robot repeats stepping motion by the center of gravity movement for the robot on lateral plane. And swinging of the leg is added to this stepping motion and a walk action is done. This paper deals with walking control algorithm by sensors and the relaxation motion of the actuators.

高軸力を受ける鉄筋コンクリート双肢柱の耐震性能に関する実験研究

高軸力を受ける鉄筋コンクリート双肢柱の耐震性能に関する実験研究

THE CONSTRUCTION OF KYLESKU BRIDGE.

Keywords OVE ARUP MORRISON CONSTRUCTION LTD BRIDGES, CONSTRUCTION, DESIGN, METHODS, FACTORS, ELEMENTS, LEGS, TECHNIQUES, SPLAYED, INCREMENTAL, PIERS, CANTILEVER, SPANS, PRECAST, SUBSTRUCTURES, MAIN, FOUNDATIONS, JOINTS, SUPPORTS, TIES, STEMS, TEMPORARY, SADDLES, STRUTS, DECKS, PRESTRESSED, STAGE, SITES, PLANT, ADMINISTRATION, EQUIPMENT KYLESKU, SCOTLAND UK... Show All