force relationship
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2022 ◽  
Vol 2148 (1) ◽  
pp. 012004
Author(s):  
Zhong Guan

Abstract There discovered the maximum possible magnetic induction in nature, equal to the magnetic induction at the poles of an electron’s spin, When the spin magnetic moments of two electrons are close to each other, they act on each other with the maximum possible magnetic induction, and finally entered the maximally entangled state after the energy drops. By this time, the spin magnetic moments on both sides situated in anti-parallel, between them there existed four invisible magnetic circuit, and each magnetic circuit just contain a fluxon. No matter how far the distance between the spins, owing to the inalienability of fluxon, no magnetic flux leakage (coupling degree 100%), so these four magnetic circuit will always existed, maintaining the maximally entangled state system immutably. This is the material basis for the entangled state to be existed, nothing to do with “spooky action at a distance”. In this paper, a visual schematic diagram has drawn to describe these, and the magnetic force state, force relationship and “light barrier” problem are analyzed.


2021 ◽  
Author(s):  
Samuel Ginot ◽  
Benedikt Hallgrímsson ◽  
Sylvie Agret ◽  
Julien Claude

AbstractFitness-related traits tend to have low heritabilities. Conversely, morphology tends to be highly heritable. Yet, many fitness-related performance traits such as running speed or bite force depend critically on morphology. Craniofacial morphology correlates with bite performance in several groups including rodents. However, within species, this relationship is less clear, and the genetics of performance, morphology and function are rarely analyzed in combination. Here, we use a half-sib design in outbred wild-derived Mus musculus to study the morphology-bite force relationship and determine whether there is additive genetic (co-)variance for these traits. Results suggest that bite force has undetectable additive genetic variance and heritability in this sample, while morphological traits related mechanically to bite force exhibit varying levels of heritability. The most heritable traits include the length of the mandible which relates to bite force. Despite its correlation with morphology, realized bite force was not heritable, which suggests it is less responsive to selection in comparison to its morphological determinants. We explain this paradox with a non-additive, many-to-one mapping hypothesis of heritable change in complex traits. We furthermore propose that performance traits could evolve if pleiotropic relationships among the determining traits are modified.


PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252644
Author(s):  
Hiroshi Akima ◽  
Hisashi Maeda ◽  
Teruhiko Koike ◽  
Koji Ishida

The electromyographic (EMG) activity and force relationship, i.e. EMG-force relationship, is a valuable indicator of the degree of the neuromuscular activation during isometric force production. However, there is minimal information available regarding the EMG-force relationship of individual triceps brachii (TB) muscles at different elbow joint angles. This study aimed to compare the EMG-force relationships of the medial (TB-Med), lateral (TB-Lat), and long heads (TB-Long) of the TB. 7 men and 10 women performed force matching isometric tasks at 20%, 40%, 60%, and 80%maximum voluntary contraction (MVC) at 60°, 90°, and 120° of extension. During the submaximal force matching tasks, the surface EMG signals of the TB-Med, TB-Lat, and TB-Long were recorded and calculated the root mean square (RMS). RMS of each force level were then normalized by RMS at 100%MVC. For the TB-Med, ultrasonography was used to determine the superficial region of the muscle that faced the skin surface to minimize cross-talk. The joint angle was monitored using an electrogoniometer. The elbow extension force, elbow joint angle, and surface EMG signals were simultaneously sampled at 2 kHz and stored on a personal computer. The RMS did not significantly differ between the three muscles, except between the TB-Med and TB-Lat during 20%MVC at 60°. The RMS during force levels of ≥ 60%MVC at 120° was significantly lower than that at 60° or 90° for each muscle. The sum of difference, which represents the difference in RMS from the identical line, did not significantly differ in any of the assessed muscles in the present study. This suggests that a relatively smaller neuromuscular activation could be required when the elbow joint angle was extended. However, neuromuscular activation levels and relative force levels were matched in all three TB synergists when the elbow joint angle was at 90° or a more flexed position.


2021 ◽  
Vol 118 (18) ◽  
pp. e2007693118
Author(s):  
Jillian K. Swencionis ◽  
Enrique R. Pouget ◽  
Phillip Atiba Goff

Three studies translate social dominance theory to policing, testing the relationship between individual officers’ endorsement of social hierarchies and their tendency to use force against residents. This article demonstrates a link between officer psychological factors and force. Because police are empowered to use force to maintain social order, and because White officers hold a dominant racial identity, we hypothesized social dominance orientation (SDO) would relate to force positively for White officers. For Black officers, we hypothesized a weak relationship between SDO and force, if any. To test these predictions, we examined the relationships between SDO and force using negative binomial regression models stratified by officer race. In an eastern city, SDO relates to force incidents positively for White officers and negatively for Black officers. In a southern city, SDO relates to force positively for White officers, and not significantly for Black officers. Stratified by race and rank, a second eastern city shows a marginally significant, positive SDO/force relationship for White patrol officers, and no significant SDO/force relationship for Black patrol officers. Finally, testing our hypotheses on a dataset pooled across these cities revealed a positive SDO/force relationship among White officers, and no significant SDO/force relationship among Black officers. These findings are consistent with our hypotheses and suggest a need to examine the role that maintaining social hierarchies plays in police behaviors. Future research must continue to investigate these relationships, especially with larger samples of non-White officers, and information about officers’ patrol environments.


2021 ◽  
pp. 1-25
Author(s):  
Hyeon-Ho Yang ◽  
Jae-Hung Han

Abstract Diverse applications including switches, deployable structures, and reconfigurable robots can benefit from bi-stability characteristics. However, the complexity of implementation and the limitation of structure configuration make it difficult to apply conventional bi-stable mechanisms to the structures that require rotational bi-stability. In this paper, an implementation method using cylindrical magnets for the rotational bi-stable mechanism is proposed. The proposed bi-stable mechanism consists of a revolute joint with two links. It has rotational bi-stability through the magnetic force relationship between the array of magnets on each link. To identify the characteristics of the proposed bi-stable mechanism, a cylindrical permanent magnet is considered as an electromagnet model that consists of one ring with a virtual electric current. The magnetic field of the cylindrical permanent magnet can be calculated using Biot-Savart law. Similarly, the magnetic force between two cylindrical permanent magnets is calculated using Lorentz force law. The criteria of the magnet array for symmetric bi-stability are described and the potential energy diagram of the rotation link is considered as the performance criterion to identify the stable state. The proposed bi-stable mechanism was applied to the prototype of a deployable structure consisting of two links. The load testing of the structure against external torque was performed and it was obtained that the rotation link can stay within 5deg angle to the maximum load applied and was experimentally verified with good agreement.


Author(s):  
F. Geßner ◽  
M. Weigold ◽  
E. Abele

AbstractFor machining internal threads, tapping is a commonly used process. However, due to the complex geometry of the tapping tool, each tooth has a unique geometry resulting in individual forces. Since the forces act synchronously during the process, they partly compensate each other. However, since resulting forces in tapping can cause undesired deflection of the tool which can lead to threads that are not true to gauge or tool breakage, the knowledge of the forces is crucial. To predict the occurring forces on each tooth, different modelling approaches can be used. An approach based on the chip load-cutting force relationship is the mechanistic modelling. Therefore, a suitable force model is of central importance. An empirical force model can be established using an analogy process. Within this work a single tooth analogy process is presented to measure the forces of each tooth separately. By means of a geometrical analysis of the real tool, the chip sizes, such as the cross-section area of the undeformed chip are calculated. Merging the measured process forces from the analogy process and the actual chip sizes, an empirical force model is set up using multivariate regression. The model is validated by implementing it in an existing framework and comparing the results to experimental data.


Author(s):  
Senhao Hou ◽  
Xiaoqiang Tang ◽  
Yuheng Wang ◽  
Dianjun Wang

Abstract During the landing and detection missions of the Moon, Mars, and asteroids, due to the complexity and unpredictability of the landing process, it is necessary and critical to carry out simulation tests on the ground to simulate the stress state during the separation of the backshell from the lander. A high-speed cable-driven mechanism adopted. The cable force is different at the end actuator and the drum. There are many factors causing this difference, such as high acceleration, cable stiffness, cable density, cable length. In this paper, the cable force transmission of spacecraft during high-speed separation is studied. The dynamic model of high-speed cable-driven mechanism is established based on Newton principle, then the trial function is introduced, and the second-order partial differential equation is solved by using the method of space discretization. The force relationship of the cable in the process of motion is obtained, and the influencing factors of the cable force are explored. Finally, the correctness of the research content in this paper is verified by numerical simulation and experiment. The results show that the model can accurately simulate the force state of the cable, and it has guiding significance for the active high-speed separation test of spacecraft.


Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2864
Author(s):  
Meng-Ju Lin ◽  
Hui-Min Chou ◽  
Rongshun Chen

Even when made by brittle materials, awl-shaped serpentine microsprings (ASSMs) were found to have a nonlinear displacement–force relationship similar to springs made by ductile material. It is found that the nonlinear displacement–force relationship is due to the geometry and dimensions of the ASSMs. The geometric effect of the nonlinear force–displacement relationship of ASSMs for in-plane motion was investigated. A theoretical solution was derived to analyze this nonlinearity. By successfully fabricating and measuring an ASSM, the theoretical results agreed well with the experimental results. The results indicated that ASSMs have a nonlinear force–displacement relationship, which is similar to that of hardening springs. The taper angle has a significant effect on the nonlinear displacement of ASSMs. When the taper angle was small, no obvious effect appeared on the nonlinearity of the microsprings with different numbers of turns. When the beam length increased, the critical force for nonlinear deflection decreased.


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