Journal articles on the topic 'Unified theory of force'
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Andrey, Chaykin. "Unified Theory of Force Fields (Electromagnetic and Gravitational)." World Journal of Condensed Matter Physics 07, no. 01 (2017): 31–35. http://dx.doi.org/10.4236/wjcmp.2017.71003.
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Chernitskii, Alexander. "Gravitation in Unified Scalar Field Theory." Universe 7, no. 1 (January 9, 2021): 11. http://dx.doi.org/10.3390/universe7010011.
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The scalar field of space-time film is considered as unified fundamental field. The field model under consideration is the space-time generalization of the model for a two-dimensional thin film. The force and metrical interactions between solitons are considered. These interactions correspond to the electromagnetic and gravitational interactions respectively. The metrical interaction and its correspondence to the gravitational one are considered in detail. The practical applications of this approach are briefly discussed.
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Chernitskii, Alexander A. "Gravitation in Unified Scalar Field Theory." Universe 7, no. 1 (January 9, 2021): 11. http://dx.doi.org/10.3390/universe7010011.
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The scalar field of space-time film is considered as unified fundamental field. The field model under consideration is the space-time generalization of the model for a two-dimensional thin film. The force and metrical interactions between solitons are considered. These interactions correspond to the electromagnetic and gravitational interactions respectively. The metrical interaction and its correspondence to the gravitational one are considered in detail. The practical applications of this approach are briefly discussed.
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Morrison, Margaret. "Reduction, Unity and the Nature of Science: Kant's Legacy?" Royal Institute of Philosophy Supplement 63 (October 2008): 37–62. http://dx.doi.org/10.1017/s1358246108000039.
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One of the hallmarks of Kantian philosophy, especially in connection with its characterization of scientific knowledge, is the importance of unity, a theme that is also the driving force behind a good deal of contemporary high energy physics. There are a variety of ways that unity figures in modern science—there is unity of method where the same kinds of mathematical techniques are used in different sciences, like physics and biology; the search for unified theories like the unification of electromagnetism and optics by Maxwell; and, more recently, the project of grand unification or the quest for a theory of everything which involves a reduction of the four fundamental forces (gravity, electromagnetism, weak and strong) under the umbrella of a single theory. In this latter case it is thought that when energies are high enough, the forces (interactions), while very different in strength, range and the types of particles on which they act, become one and the same force. The fact that these interactions are known to have many underlying mathematical features in common suggests that they can all be described by a unified field theory. Such a theory describes elementary particles in terms of force fields which further unifies all the interactions by treating particles and interactions in a technically and conceptually similar way. It is this theoretical framework that allows for the prediction that measurements made at a certain energy level will supposedly indicate that there is only one type of force. In other words, not only is there an ontological reduction of the forces themselves but the mathematical framework used to describe the fields associated with these forces facilitates their description in a unified theory. Specific types of symmetries serve an important function in establishing these kinds of unity, not only in the construction of quantum field theories but also in the classification of particles; classifications that can lead to new predictions and new ways of understanding properties like quantum numbers. Hence, in order to address issues about unification and reduction in contemporary physics we must also address the way that symmetries facilitate these processes.
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Antoniadis, I. "Quarks and a unified theory of Nature fundamental forces." International Journal of Modern Physics A 30, no. 02 (January 20, 2015): 1530015. http://dx.doi.org/10.1142/s0217751x1530015x.
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Quarks were introduced 50 years ago opening the road towards our understanding of the elementary constituents of matter and their fundamental interactions. Since then, a spectacular progress has been made with important discoveries that led to the establishment of the Standard Theory that describes accurately the basic constituents of the observable matter, namely quarks and leptons, interacting with the exchange of three fundamental forces, the weak, electromagnetic and strong force. Particle physics is now entering a new era driven by the quest of understanding of the composition of our Universe such as the unobservable (dark) matter, the hierarchy of masses and forces, the unification of all fundamental interactions with gravity in a consistent quantum framework, and several other important questions. A candidate theory providing answers to many of these questions is string theory that replaces the notion of point particles by extended objects, such as closed and open strings. In this short note, I will give a brief overview of string unification, describe in particular how quarks and leptons can emerge and discuss what are possible predictions for particle physics and cosmology that could test these ideas.
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Ji, Jing, Wen Fu Zhang, and Hai Yan Sui. "Experimental Verification on Bearing Capacity of Concrete-Filled Steel Tube Short Columns Based on Unified Theory." Advanced Materials Research 163-167 (December 2010): 1999–2004. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.1999.
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To verify the rationality of calculation method on unified theory of concrete - filled steel tube short columns under axial force, Experimental Study on mechanical properties of the 12 concrete -filled steel tube short columns with 7 different sections under axial force is preformed. Failure process and Failure mode of them are observed, load-displacement curves are obtained, and the influence for confinement coefficient ξ to the mechanical properties of short columns under axial load is analyzed. Based on load-displacement curves, ultimate bearing capacities of them are given. By comparison for ultimate bearing capacity obtained by testing and the bearing capacity according to unified theory, the results show both are in good agreement. Calculation method on unified theory of concrete - filled steel tube is fit for calculating ultimate bearing capacity of short columns under axial force with different sections, and the results are safe and reliable.
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Zhang, Pei, Huiting Xiong, and Junsheng Chen. "Unified Fundamental Formulas for Static Analysis of Pin-Jointed Bar Assemblies." Symmetry 12, no. 6 (June 10, 2020): 994. http://dx.doi.org/10.3390/sym12060994.
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The initial axial forces of members—whatever caused by prestress or external loads—may strongly change the mechanical properties of pin-jointed bar assemblies, to enhance, or even establish their structural stiffness. The structural responses under external disturbance cannot be calculated accurately if the influence of initial axial forces has not been considered appropriately. In this paper, an analytic theory considering the effect of initial internal forces is developed on the basis of linear elasticity hypothesis. The fundamental formulas proposed finally include generalized equilibrium equations and generalized compatibility equations, both of which have square coefficient matrices of full rank being transposed with each other. Generally, this method can be regarded as an extended version of a traditional force method considering the stiffening effect of initial internal forces. Compared with the matrix force method, it has a wider application scenario since few redundant simplifications are employed in the derivation of the formulas. In comparison with the displacement-based algorithm, the proposed method has the inherent advantages of the force method—the physical concepts of each item in equations are fairly explicit; and the combination coefficients of self-stress states and mechanisms are determined simultaneously in solving the structural responses. Thus, it is very helpful for us to essentially comprehend the principle that the pin-jointed bar assemblies resist the external loads.
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Vayenas, Constantinos G. "The Standard Model (SM) and the goal of force unification." Open Access Government 37, no. 1 (January 6, 2023): 228–31. http://dx.doi.org/10.56367/oag-037-10539.
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The Standard Model (SM) and the goal of force unification The unification of gravitational, Strong and Weak Forces has been a long-sought goal [1-3]. In general, force unification refers to the idea that it is possible to view all of the forces of nature as manifestations of one single, all-encompassing force. Today, within the context of the Standard Model (SM) of elementary particles, [7] scientists seek to unify Gravity with the Strong force under a Grand Unified Theory which binds quarks together and is responsible for the stability of atomic nuclei. These efforts have not been successful yet, most likely because the SM neglects neutrinos [8,9], gravity [4], special relativity [10] and quantum mechanics [11].
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Lamsal, Min Raj. "Supersymmetry." Himalayan Physics 4 (December 23, 2013): 75–79. http://dx.doi.org/10.3126/hj.v4i0.9432.
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This article deals with the introduction of supersymmetry as the latest and most emerging burning issue for the explanation of nature including elementary particles as well as the universe. Supersymmetry is a conjectured symmetry of space and time. It has been a very popular idea among theoretical physicists. It is nearly an article of faith among elementary-particle physicists that the four fundamental physical forces in nature ultimately derive from a single force. For years scientists have tried to construct a Grand Unified Theory showing this basic unity. Physicists have already unified the electron-magnetic and weak forces in an 'electroweak' theory, and recent work has focused on trying to include the strong force. Gravity is much harder to handle, but work continues on that, as well. In the world of everyday experience, the strengths of the forces are very different, leading physicists to conclude that their convergence could occur only at very high energies, such as those existing in the earliest moments of the universe, just after the Big Bang.The Himalayan Physics Vol. 4, No. 4, 2013 Page: 75-79 Uploaded date: 12/23/2013
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Song, Zhiqiang, Fei Wang, Yujie Liu, and Chenhui Su. "Infinite Element Static-Dynamic Unified Artificial Boundary." Shock and Vibration 2018 (July 5, 2018): 1–14. http://dx.doi.org/10.1155/2018/7828267.
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The method, which obtains a static-dynamic comprehensive effect from superposing static and dynamic effects, is inapplicable to large deformation and nonlinear elastic problems under strong earthquake action. The static and dynamic effects must be analyzed in a unified way. These effects involve a static-dynamic boundary transformation problem or a static-dynamic boundary unified problem. The static-dynamic boundary conversion method is tedious. If the node restraint reaction force caused by a static boundary condition is not applied, then the model is not balanced at zero moment, and the calculation result is distorted. The static numerical solution error is large when the structure possesses tangential static force in a viscoelastic static-dynamic unified boundary. This paper proposed a new static-dynamic unified artificial boundary based on an infinite element in ABAQUS to solve static-dynamic synthesis effects conveniently and accurately. The static and dynamic mapping theories of infinite elements were introduced. The characteristic of the infinite element, which has zero displacement at faraway infinity, was discussed in theory. The equivalent nodal force calculation formula of infinite element unified boundary was deduced from an external wave input. A calculation and application program of equivalent nodal forces was developed using the Python language to complete external wave inputting. This new method does not require a static and dynamic boundary transformation and import of stress field and constraint counterforce of boundary nodes. The static calculation precision of the infinite element unified boundary is more improved than the viscoelastic static-dynamic unified boundary, especially when the static load is in the tangential direction. In addition, the foundation simulation range of finite field can be significantly reduced given the utilization of the infinite element static dynamic unified boundary. The preciseness of static calculation and dynamic calculation and static-dynamic comprehensive analysis are unaffected.
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Feld, Lea, Lior Kellerman, Abhishek Mukherjee, Ariel Livne, Eran Bouchbinder, and Haguy Wolfenson. "Cellular contractile forces are nonmechanosensitive." Science Advances 6, no. 17 (April 2020): eaaz6997. http://dx.doi.org/10.1126/sciadv.aaz6997.
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Cells’ ability to apply contractile forces to their environment and to sense its mechanical properties (e.g., rigidity) are among their most fundamental features. Yet, the interrelations between contractility and mechanosensing, in particular, whether contractile force generation depends on mechanosensing, are not understood. We use theory and extensive experiments to study the time evolution of cellular contractile forces and show that they are generated by time-dependent actomyosin contractile displacements that are independent of the environment’s rigidity. Consequently, contractile forces are nonmechanosensitive. We further show that the force-generating displacements are directly related to the evolution of the actomyosin network, most notably to the time-dependent concentration of F-actin. The emerging picture of force generation and mechanosensitivity offers a unified framework for understanding contractility.
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Lin, Y. L., and T. Liu. "A Unified Approach for the Kinematic and Force Analysis of Simple Wire-Driven Platform Mechanisms." Journal of Mechanics 20, no. 3 (September 2004): 211–17. http://dx.doi.org/10.1017/s1727719100003427.
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AbstractIn the analysis of simple wire-driven platform (SWDP) mechanisms, the tension and the posture of each wire can be formulated, and expressed in an integrated screw representation naturally. In this study, a unified approach for analyzing the kinematics and kinetics of SWDP mechanisms based on the screw theory is proposed and developed, which includes the screw-based Jacobian, the static and dynamic equilibrium of wires and platform, and the singularity analysis. Via using the unified screw-based approach, the investigation on the characteristics of SWDP mechanisms, therefore, can be more efficient and simplified. An example is presented to demonstrate this unified approach.
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Jasso, G. "A New Unified Theory of Sociobehavioural Forces." European Sociological Review 24, no. 4 (May 21, 2008): 411–34. http://dx.doi.org/10.1093/esr/jcn023.
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Tyurin, Vitalii,, Volodymyr, Mirnenko, Anatolii, Salii, Pavlo, Openʹko, and Oleksandr, Avramenko. "Reviews on the development of the theory of logistic support of the Air Force of the Armed Forces of Ukraine." VUZF REVIEW 4, no. 4 (December 31, 2019): 58–67. http://dx.doi.org/10.38188/2534-9228.19.4.06.
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The existing separate arms theory and the theory of the Logistics of the Armed Forces as components of military science lose their functional purpose as partial theories in modern conditions of operations (combat actions).The article proposes a unified theory of logistics of the Air Forces of the Armed Forces of Ukraine, based on the existing theories of armament and the logistics of the Armed Forces, based on the general laws and established consistent patterns, trends, principles, forms and methods of the use of the logistics of the Air Forces of the Armed Forces of Ukraine. The objective function of the logistics system of the Air Forces of the Armed Forces of Ukraine is formulated, which is to achieve compliance of the capabilities of this system with the predicted volume of tasks of the logistics. In order to implement this compliance it is necessary to ensure the convergence of requirements and capabilities at all levels of logistics management.The purpose of the article is to determine the main provisions of the new unified theory of logistics of the Air Forces of the Armed Forces of Ukraine taking into account modern forms and methods of conducting operations (combat actions), requirements concerning the formation of a unified logistics system of the Armed Forces of Ukraine and logistic support, created management bodies, forces and assets of military units (formations) logistics of the Air Forces of the Armed Forces of Ukraine.The assessment of the functioning of the Air Forces logistics system of the Armed Forces of Ukraine is proposed on the basis of the stated views on the logistics theory of the Air Forces of the Armed Forces of Ukraine by assessing the set of real capabilities of each subsystem that is the part of its structure and system as a whole. At the same time, the assessment of the quality of the logistic support of the military units (formations) of the Air Forces of the Armed Forces of Ukraine should be related to the level of implementation of the potential capabilities of the logistics system when solving problems of each subsystem at the stages of combat training, unblocking and operational deployment, preparation and conduct of operations (combat actions), restoration of combat capability of troops (forces).
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Taber, Larry A. "Towards a unified theory for morphomechanics." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 367, no. 1902 (September 13, 2009): 3555–83. http://dx.doi.org/10.1098/rsta.2009.0100.
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Mechanical forces are closely involved in the construction of an embryo. Experiments have suggested that mechanical feedback plays a role in regulating these forces, but the nature of this feedback is poorly understood. Here, we propose a general principle for the mechanics of morphogenesis, as governed by a pair of evolution equations based on feedback from tissue stress. In one equation, the rate of growth (or contraction) depends on the difference between the current tissue stress and a target (homeostatic) stress. In the other equation, the target stress changes at a rate that depends on the same stress difference. The parameters in these morphomechanical laws are assumed to depend on stress rate. Computational models are used to illustrate how these equations can capture a relatively wide range of behaviours observed in developing embryos, as well as show the limitations of this theory. Specific applications include growth of pressure vessels (e.g. the heart, arteries and brain), wound healing and sea urchin gastrulation. Understanding the fundamental principles of tissue construction can help engineers design new strategies for creating replacement tissues and organs in vitro .
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Pontzer, Herman. "A unified theory for the energy cost of legged locomotion." Biology Letters 12, no. 2 (February 2016): 20150935. http://dx.doi.org/10.1098/rsbl.2015.0935.
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Small animals are remarkably efficient climbers but comparatively poor runners, a well-established phenomenon in locomotor energetics that drives size-related differences in locomotor ecology yet remains poorly understood. Here, I derive the energy cost of legged locomotion from two complementary components of muscle metabolism, Activation–Relaxation and Cross-bridge cycling. A mathematical model incorporating these costs explains observed patterns of locomotor cost both within and between species, across a broad range of animals (insects to ungulates), for a wide range of substrate slopes including level running and vertical climbing. This ARC model unifies work- and force-based models for locomotor cost and integrates whole-organism locomotor cost with cellular muscle physiology, creating a predictive framework for investigating evolutionary and ecological pressures shaping limb design and ranging behaviour.
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OU-YANG, ZHONG-CAN. "THE ELASTIC THEORY OF SINGLE-MOLECULE DNA." International Journal of Modern Physics B 17, no. 01n02 (January 20, 2003): 69–75. http://dx.doi.org/10.1142/s0217979203017102.
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Our recent work on the elastic responses of double- (ds) and single-stranded (ss) DNA at external force fields is reviewed. By constructing as elastic model of dsDNA in which the base-pair stacking interaction is included, we demonstrate that dsDNA entropic elasticity, cooperative extensibility, and supercoiling property can all be understood from a unified viewpoint. The base-pair stacking interaction is also found to determine the cooperativity of the stretch-induced hairpin-coil transition is ssDNA.
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Wang, Xiang Qiu, and Wen Tao Yang. "Study on the Bearing Capacity of Slime Friction Pile Based on the Double-Sheared Theory." Applied Mechanics and Materials 353-356 (August 2013): 1005–10. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.1005.
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The bearing capacity of slime friction pile based on the Mohr-Coulombs strength criterion couldnt make full use of the potential strengths ability of rock-soil. But the double shear unified strength theory can depict really the bearing characteristics of rock-soil because it can consider the effect of intermediate principal stress comprehensively. On this condition, based on the Mindlins displacement solution and the double shear unified strength theory, a calculated formula of bearing capacity was proposed for the slime friction pile, and then the distribution regularities of lateral friction-resistance force for the slime friction pile were discussed.
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Huang, Wei, Cheng Hua Zhang, Qian Feng Yao, Guo Xin Chen, and Hao Zhen Wu. "Calculation Analysis on Cracking Load of New Type Composite Wall." Advanced Materials Research 163-167 (December 2010): 1012–18. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.1012.
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New type composite wall is the main bearing member in Multi-ribbed Slab Structure (MRSS), whose cracking load is an important parameter to determine the restoring force model and damage index of the wall. Based on the twin shear unified strength theory, when the influence of intermediate principal stress σ2 and SD effect of materials are considered, the study on low-frequency cyclic lateral loading experiment of wall is proceed and the practical formula for the wall’s initial cracking load is deduced. The practical computing formulas for the wall’s initial cracking load based on twin shear unified strength theory and maximum tensile stress theory are contrastingly analyzed. The results show that, comparing the calculated values based on the twin shear unified strength theory and the values based on maximum tensile stress theory, the former are more closed to the experimental values, and it can provide more accurate, economic and applicable results for practical engineering.
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Winter, D. A., F. Prince, J. S. Frank, C. Powell, and K. F. Zabjek. "Unified theory regarding A/P and M/L balance in quiet stance." Journal of Neurophysiology 75, no. 6 (June 1, 1996): 2334–43. http://dx.doi.org/10.1152/jn.1996.75.6.2334.
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1. Control of posture in quiet stance has been quantified by center of pressure (COP) changes in the anterior-posterior (A/P) and medial-lateral (M/L) directions from a single force platform. Recording from a single force platform, researchers are unable to recognize two separate mechanisms that become evident when two force platforms are used. Depending on the stance position taken, many combinations of an ankle mechanism and a hip (load/unload) mechanism are evident. In side-by-side stance, A/P balance is totally under ankle (plantar/dorsiflexor) control, whereas M/L balance is under hip (abductor/adductor) control. In tandem stance, the A/P balance is dominated by the hip mechanism, with mixed and small or sometimes negligible contributions by the ankle plantar/dorsiflexors: for M/L balance, the reverse is evident; ankle invertors/evertors dominate, with mixed and small contribution from the hip load/unload mechanism. In an intermediate 45 degrees stance position, both ankle and hip mechanisms contribute to the net balance control in totally different ways. In the M/L direction the two strategies reinforce, whereas in the A/P direction the ankle mechanism must overcome and cancel most of the inappropriate contribution by the hip load/unload mechanism. A spatial plot of the separate mechanisms reveals the fact that the random-looking COP scatter plot is nothing more than a spatial and temporal summation of two separate spatial plots. A straight line joining the individual COPs under each foot is the load/unload line controlled by the hip mechanism. At right angles to this load/unload line in the side-by-side and tandem positions is the independent control line by the ankle muscles. In an intermediate standing position, the separate control lines exist, but now the ankle control is not orthogonal to the load/unload line; rather, it acts at an angle of approximately 60 degrees. The direction of these ankle control and load/unload lines also allows us to pinpoint the muscle groups responsible at the ankle and hip in any of the stance positions.
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Liu, L. Q., Y. P. Shi, J. Y. Zhu, W. D. Su, S. F. Zou, and J. Z. Wu. "Longitudinal–transverse aerodynamic force in viscous compressible complex flow." Journal of Fluid Mechanics 756 (September 1, 2014): 226–51. http://dx.doi.org/10.1017/jfm.2014.403.
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AbstractWe report our systematic development of a general and exact theory for diagnosis of total force and moment exerted on a generic body moving and deforming in a calorically perfect gas. The total force and moment consist of a longitudinal part (L-force) due to compressibility and irreversible thermodynamics, and a transverse part (T-force) due to shearing. The latter exists in incompressible flow but is now modulated by the former. The theory represents a full extension of a unified incompressible diagnosis theory of the same type developed by J. Z. Wu and coworkers to compressible flow, with Mach number ranging from low-subsonic to moderate-supersonic flows. Combined with computational fluid dynamics (CFD) simulation, the theory permits quantitative identification of various complex flow structures and processes responsible for the forces, and thereby enables rational optimal configuration design and flow control. The theory is confirmed by a numerical simulation of circular-cylinder flow in the range of free-stream Mach number $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}M_{\infty }$ between 0.2 and 2.0. The L-drag and T-drag of the cylinder vary with $M_{\infty }$ in different ways, the underlying physical mechanisms of which are analysed. Moreover, each L-force and T-force integrand contains a universal factor of local Mach number $M$. Our preliminary tests suggest that the possibility of finding new similarity rules for each force constituent could be quite promising.
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Chang, Yongbin, and Larry A. Viehland. "The cumulative measure of a force: A unified kinetic theory for rigid-sphere and inverse-square force law interactions." AIP Advances 1, no. 3 (September 2011): 032128. http://dx.doi.org/10.1063/1.3625406.
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A, Etkin, V. "To the Theory of a Unified Field." Scholars Journal of Engineering and Technology 9, no. 10 (November 18, 2021): 168–75. http://dx.doi.org/10.36347/sjet.2021.v09i10.003.
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Maxwell-like equations are offered that are valid not only for electromagnetic, but also for gravitational fields. They are based on an expanded form of the law of energy conversion, which explicitly takes into account the nonequilibrium of systems and the ability of energy to transfer from one energy carrier to another. This makes it possible to eliminate the distinction between electromechanics and the field theory, to find out the meaning of the magnetic vector potential as a function of the charge rotation speed, to reveal the tensor nature of the magnetic field and the presence of a divergent component of the scalar nature in it. The existence of the Lorentz magnetic forces and the presence of a work-performing moment therein are proved. Maxwell-like equations do not contain field operators and have a simpler form covering nevertheless a broader spectrum of phenomena due to taking into account the convective components of bias currents. Wave equations alternative to the Maxwell ones are offered and the non-electromagnetic nature of light is substantiated.
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Kalies, Grit. "Back to the roots: the concepts of force and energy." Zeitschrift für Physikalische Chemie 236, no. 4 (November 29, 2021): 481–533. http://dx.doi.org/10.1515/zpch-2021-3122.
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Abstract The concepts of force and energy are analyzed in the context of state and process equations. In chronological order, the application of the cause-effect principle in process equations is studied in mechanics, thermodynamics, special relativity, general relativity, and quantum theory. The differences in the fundamental approaches to nature and the significance of a consistent physical interpretation of formulas and state variables are emphasized. It is shown that the first origins for the crisis of modern theoretical physics are to be found in the concepts of force and energy in mechanics, which partly violate the cause-effect principle. This affects all theories based on mechanics and underlines their historical conditionality. The systematic application of driving forces and the cause-effect principle in process equations suggests a return to causal realistic physics. It meets the wave character of matter, is compatible with the experiment, and allows a unified description of interaction.
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Bagci, C. "A New Unified Strength of Materials Solution for Stresses in Curved Beams and Rings." Journal of Mechanical Design 114, no. 2 (June 1, 1992): 231–37. http://dx.doi.org/10.1115/1.2916936.
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Presently existing strength of materials solutions for stresses in curved beams use an incorrect normal force equilibrium condition to define neutral axis location, and to reach a simplified solution, which neglects the curvature effect on stresses due to normal force. This article presents a new but a most general form of the strength of materials solution for determining tangential normal stresses in curved beams, including reductions to special cases. The neutral axis phenomenon is clarified and experimentally verified. Several numerical examples are included, some of which offer photoelastic experimental results, where results predicted by the exact elasticity solution, method of the article, Winkler’s theory, and the conventional simplified method are compared. The hook, diametrically loaded cut, and full ring applications are included. It is shown that simplified theory leads to very large errors. Results by the method offered are very reliable with small errors which are comparable with those of exact elasticity solutions. Stress and deflection analyses of curved beams with varying thicknesses of cross-sections by exact elasticity solutions are given in a separate article [6].
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KOIKE, Yasuharu. "Unified Theory of Motor Learning : A Control Model for Motion and Force Generation and Its Applications." Japanese Journal of Rehabilitation Medicine 52, no. 3 (2015): 195–97. http://dx.doi.org/10.2490/jjrmc.52.195.
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Liang, Guanqun, Yan Wang, Mario A. Garcia, Tong Zhao, Zhe Liu, Michael Kaliske, and Yintao Wei. "A Universal Approach to Tire Forces Estimation by Accelerometer-Based Intelligent Tire: Analytical Model and Experimental Validation." Tire Science and Technology 50, no. 1 (October 19, 2021): 2–26. http://dx.doi.org/10.2346/tire.21.21001.
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ABSTRACT Efforts to improve the performance and safety of vehicles include placing active sensing components (e.g., embedded microsensors) within tires result in intelligent tires. One application of intelligent tire is tire force estimation based on accelerometers. However, its development is limited due to the difficulty of relating the tire force to kinematical information by model-based theory. In this manuscript, a universal approach to tire forces estimation by the accelerometer-based intelligent tire is formulated and experimentally validated. First, a microelectromechanical system accelerometer-based intelligent tire prototype is established with the function of on-board monitoring of tire forces. Then, a theoretical rolling kinematics model is proposed for illustrating the mechanisms of acceleration fields, resulting from the coupling effect of rigid body motion and elastic deformation. An analytical model is formulated to estimate the vertical force in real time. Furthermore, the beam model is adopted to describe lateral deformations of the tire belt, directly linking lateral acceleration and lateral force. Finally, the lateral force can be estimated by lateral acceleration and vertical force already estimated. Based on a universal analytical model, the lateral force estimation method realizes high accuracy under different circumstances, even with unified coefficients, by clarifying and eliminating the influence of ply steer. A field test and two bench experiments have been conducted to fully validate the developed model. It can be concluded that the theoretical-analysis-based estimation model realizes an encouraging tire force estimation application with an intelligent tire hardware system.
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Hernández Morales, Hernán Martín. "Modelling lead-rubber seismic isolation bearings using the unified mechanics theory." Journal of Structural Engineering & Applied Mechanics 4, no. 4 (December 31, 2021): 213–26. http://dx.doi.org/10.31462/jseam.2021.04213226.
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Lead-rubber seismic isolation bearings (LRB) have been installed in a number of essential and critical structures, like hospitals, universities and bridges, in order to provide them with period lengthening and the capacity of dissipating a considerable amount of energy to mitigate the effects of strong ground motions. Therefore, studying the damage mechanics of this kind of devices is fundamental to understand and accurately describe their thermo-mechanical behavior, so that seismically isolated structures can be designed more safely. Hitherto, the hysteretic behavior of LRB has been modeled using 1) Newtonian mechanics and empirical curve fitting degradation functions, or 2) heat conduction theories and idealized bilinear curves which include degradation effects. The reason for using models that are essentially phenomenological or that contain some adjusted parameters is the fact that Newton’s universal laws of motion lack the term to account for degradation and energy loss of a system. In this paper, the Unified Mechanics Theory – which integrates laws of Thermodynamics and Newtonian mechanics – is used to model the force-displacement response of LRB. Indeed, there is no need for curve fitting techniques to describe their damage behavior because degradation is calculated at every point using entropy generation along the Thermodynamics State Index (TSI) axis. A finite element model of a lead-rubber bearing was constructed in ABAQUS, where a user material subroutine UMAT was implemented to define the Unified Mechanics Theory equations and the viscoplastic constitutive model for lead. Finite element analysis results were compared with experimental test data.
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Bode, Niels, Silvia Viola Kusminskiy, Reinhold Egger, and Felix von Oppen. "Current-induced forces in mesoscopic systems: A scattering-matrix approach." Beilstein Journal of Nanotechnology 3 (February 20, 2012): 144–62. http://dx.doi.org/10.3762/bjnano.3.15.
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Nanoelectromechanical systems are characterized by an intimate connection between electronic and mechanical degrees of freedom. Due to the nanoscopic scale, current flowing through the system noticeably impacts upons the vibrational dynamics of the device, complementing the effect of the vibrational modes on the electronic dynamics. We employ the scattering-matrix approach to quantum transport in order to develop a unified theory of nanoelectromechanical systems out of equilibrium. For a slow mechanical mode the current can be obtained from the Landauer–Büttiker formula in the strictly adiabatic limit. The leading correction to the adiabatic limit reduces to Brouwer’s formula for the current of a quantum pump in the absence of a bias voltage. The principal results of the present paper are the scattering-matrix expressions for the current-induced forces acting on the mechanical degrees of freedom. These forces control the Langevin dynamics of the mechanical modes. Specifically, we derive expressions for the (typically nonconservative) mean force, for the (possibly negative) damping force, an effective “Lorentz” force that exists even for time-reversal-invariant systems, and the fluctuating Langevin force originating from Nyquist and shot noise of the current flow. We apply our general formalism to several simple models that illustrate the peculiar nature of the current-induced forces. Specifically, we find that in out-of-equilibrium situations the current-induced forces can destabilize the mechanical vibrations and cause limit-cycle dynamics.
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Gerbert, G. "Belt Slip—A Unified Approach." Journal of Mechanical Design 118, no. 3 (September 1, 1996): 432–38. http://dx.doi.org/10.1115/1.2826904.
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Slip measurements on thick flat belts, V-belts and V-ribbed belts running on small pulleys reveal that the slip is much higher than can be predicted with classical creep theory. Shear creep plays an important role and special care must be taken when analyzing the shear deflection of the V-belt and the ribs of the V-ribbed belt. Other mechanisms are present as well. The behavior in the seating and unseating regions changes the direction of the frictional forces in these regions on the driver pulley. A unified slip theory is presented for flat belts, V-belts and V-ribbed belts considering creep, shear, seating/unseating and compliance. Measurements and theory fit very well for practical tension levels. At low tension the measured slip is higher than the predicted one for V-belts and V-ribbed belts, which probably depends on the poor fit between the belt and the grooved pulley.
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Blondeaux, P., and G. Seminara. "A unified bar–bend theory of river meanders." Journal of Fluid Mechanics 157 (August 1985): 449–70. http://dx.doi.org/10.1017/s0022112085002440.
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A two-dimensional model of flow and bed topography in sinuous channels with erodible boundaries is developed and applied in order to investigate the mechanism of meander initiation. By reexamining the problem recently tackled by Ikeda, Parker & Sawai (1981), a previously undiscovered ‘resonance’ phenomenon is detected which occurs when the values of the relevant parameters fall within a neighbourhood of certain critical values. It is suggested that the above resonance controls the bend growth, and it is shown that it is connected in some sense with bar instability. In fact, by performing a linear stability analysis of flow in straight erodible channels, resonant flow in sinuous channels is shown to occur when curvature ‘forces’ a ‘natural’ solution represented by approximately steady perturbations of the alternate bar type. A comparison with experimental observations appears to support the idea that resonance is associated with meander formation.
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Winterberg, F. "Substratum Approach to a Unified Theory of Elementary Particles." Zeitschrift für Naturforschung A 43, no. 12 (December 1, 1988): 1131–50. http://dx.doi.org/10.1515/zna-1988-1219.
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If special relativity is a dynamic symmetry caused by true physical deformations of bodies in absolute motion through a substratum or ether, the question if all interactions and elementary particles arc excitations of this ether must be raised. The ether being the cause of all the observed relativistic effects should then obey an exactly nonrelativistic law of motion, and which permits it to consist of positive and negative masses. The fundamental constants of nature, which according to Planck are 1) Newton's constant (G), 2) the velocity of light (c) and 3) Planck’s constant (ћ), suggest that the ether is made up of densely packed positive and negative Planck masses (Planckions), each with a diameter equaling the Planck length. Symmetry demands that the number of positive and negative Planck masses should be equal, making the cosmological constant equal to zero. Because the Planckions are nonrelativistic spin-zero bosons, the ether would therefore consist of two superfluids, one for the positive mass Planckions, and the other one for the negative mass Planckions. By spontaneous symmetry breaking this superfluid ether can in its ground state form a lattice of small vortex rings, with the vortex core radius equaling the Planck length. Force fields of massless vector gauge bosons can be interpreted as quantized transverse vortex waves propagating through this lattice. Because the smallest wave length would be about equal the ring radius of the circular vortices, the ring radius would assume the role of a unification scale. The ring radius is estimated to be about 103 times the Planck length, in fairly good agreement with the empirical evidence for the value of the grand unification scale of the standard model.Charge is explained by the zero point fluctuations of the Planckions attached to the vortex rings, wrhich thereby become the source of virtual phonons. Charge quantization is explained as the result of circulation quantization. Spinors result from bound states of the positive and negative masses of the substratum, and special relativity as a dynamic symmetry would be valid for all those objects. Quantum electrodynamics is derived as a low energy approximationIf spinors are made up from the positive and negative masses of the vortex ring resonance energy, whereby the spinors would assume the character of excitons, the spinor mass can be computed in terms of the Planck mass. Vice versa, with the lowest quark mass m given, a value for the gravitational constant in terms of m, ћ, and c can be obtained. The existence of different particle families can be understood by internal excitations of the spinors, and parity violation may find its explanation in a small nonzero vorticity of the ether. Bacause of its simple fundamental symmetry the theory is unique, it is always finite and has no anomalies.In the proposed theory all fields and interactions are explained in a completely mechanistic way by the Planck masses and their contact interactions. With special relativity as a derived dynamic symmetry and space remaining euclidean, the proposed approach can be seen as an alternative to Einstein’s program to explain all fields and their interactions by symmetries and singularities of a noneuclidean spacetime manifold.In Part I, the fundamental equation for the substratum, which has the form of a nonrelativistic nonlinear Heisenberg equation, is formulated. It is shown how it leads to a Maxwell-type set of equations for the gauge bosons. In Part II, Dirac-type spinors and quantum electrodynamics are derived. These results are then applied to obtain the lowest quark mass in terms of the Planck mass.
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Wu, Chen, Baochang Shi, Zhenhua Chai, and Peng Wang. "Discrete unified gas kinetic scheme with a force term for incompressible fluid flows." Computers & Mathematics with Applications 71, no. 12 (June 2016): 2608–29. http://dx.doi.org/10.1016/j.camwa.2016.04.025.
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Wachutka, Gerhard. "UNIFIED FRAMEWORK FOR THERMAL, ELECTRICAL, MAGNETIC, AND OPTICAL SEMICONDUCTOR DEVICE MODELING." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 10, no. 4 (April 1, 1991): 311–21. http://dx.doi.org/10.1108/eb051708.
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The “thermodynamic model” constitutes a unified theoretical framework for the coupled simulation of carrier and energy flow in semiconductor devices under general ambient conditions such as, e.g., the presence of a quasi‐static magnetic field or the interaction with an electromagnetic radiation field (light). The current relations governing particle and heat transport are derived from the principles of irreversible phenomenological thermodynamics; the driving forces include drift, diffusion, thermal diffusion, and deflection by the Lorentz force. All transport coefficients may be interpreted in terms of well‐known thermodynamic effects and, hence, can be obtained from theoretical calculations as well as directly from experimental data. The thermodynamic model allows the consistent treatment of a wide variety of physical phenomena which are relevant for both the operation of electronic devices (e.g., lattice heating, hot carrier and low temperature effects) and the function of microsensors and actuators (e.g., thermoelectricity, galvanomagnetism and thermomagnetism).
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Sinaiko, Elia A. "Quantum gravity." Physics Essays 32, no. 3 (September 9, 2019): 318–22. http://dx.doi.org/10.4006/0836-1398-32.3.318.
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Gravity has been shown in theories of relativity to be the curving of space around massive bodies. Thus, objects in orbits are following a straight line along a curved space. Why massive bodies curve space is not explained. We continue to ask “What is Gravity?” Quantum mechanics unites theories of electro-magnetism (QED), the weak nuclear force (EWT), and the strong nuclear force (QCD) in the standard model of particle physics, or with a grand unified theory (GUT) sought for these three fundamental forces. As yet there is no empirically verified quantum theory of gravity unified with these three fundamental forces. Considering gravity to be the curving of space, it is evident that gravity supervenes from the properties of space itself. In this short paper, we will attempt to define one of these spatial properties. We will not attempt to define the properties of time, though time appears to be a part of a complete model of gravity. At least in this regard, and likely in many others, our model will be incomplete. We will build a case for the massive collapse of probability density waves (PDWs) in surrounding space, due to the interactions of particles in massive bodies. The collapse of these probabilities, of each particle’s possible superposition somewhere in the surrounding space, causes the apparent “curving” of space. We will conclude that space is not the absence of things. Space is a thing in itself. Included in the properties of space is the potential to contain/transmit PDWs. This potential is suggested by both the theories of relativity and the experimental observations of quantum mechanics. In the presence of massive bodies, particle superposition and the probability of existence in the surrounding space is, to varying degrees, lost and space appears to curve as a consequence.
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Winterberg, F. "Maxwell's Equations and Einstein-Gravity in the Planck Aether Model of a Unified Field Theory." Zeitschrift für Naturforschung A 45, no. 9-10 (October 1, 1990): 1102–16. http://dx.doi.org/10.1515/zna-1990-9-1008.
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Abstract In the Planck aether substratum model it is assumed that space is densely filled with both positive and negative Planck masses described by a nonlinear nonrelativistic operator field equation. With-out expenditure of energy this substratum can form a lattice of vortex rings, with the vortex core radius equal the Planck length. The vortex ring radius is determined by a universal minimum energy quantum Reynolds number, making the ring radius and lattice spacing about 10 3 -10 4 times larger than the Planck length. The zero point fluctuations of the Planck masses bound in the vortex filaments become the source of virtual compression waves, which if quantized lead to Newton's law of gravitation, including the correct value for the gravitational constant. This scalar gravitational force couples the vortex rings, which thereby can transmit two types of transverse waves through the vortex lattice. The first type involves the tilting of the vortex rings and can be described by Maxwell's electromagnetic field equations. The second type involves the elliptic deformation of the rings and can be described by Einstein's gravitational field equations. Einstein gravity is therefore explained as resulting from the symmetric, and Maxwell's electromagnetism from the antisymmetric distor-tions of the Planck aether. Special relativity follows as a dynamic symmetry for objects held together by electromagnetic forces, and general relativity if these objects are placed in a gravitational field. Both special and general relativity, though, turn out to be low energy approximations, breaking down near the Planck scale, eliminating all divergences and singularities. Finally, the large difference between the electromagnetic and gravitational coupling constants is quantitatively explained to result from the negative masses in the Planck aether.
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MIRNENKO, Volodymyr, Pavlo OPENKO, Vitalii TIURIN, and Oleksii MARTYNIUK. "Methodological Basis of Logistic Support of the Air Force of the Armed Forces of Ukraine." Safety & Defense 5, no. 2 (January 30, 2020): 47–53. http://dx.doi.org/10.37105/sd.56.
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This article proposes a unified theory of logistics for the Air Forces of the Armed Forces of Ukraine based on the existing theories of armament and the logistics of the Armed Forces, and on the general laws and established consistent patterns, trends, principles, forms and methods of the use of the logistics of the Air Forces of the Armed Forces of Ukraine. The objective function of the logistics system of the Air Forces of the Armed Forces of Ukraine is formulated to achieve compliance of the capabilities of this system with the predicted volume of logistics tasks. In order to implement this compliance, it is necessary to ensure the convergence of requirements and capabilities at all levels of logistics management. The assessment of the functioning of the Air Forces logistics system of the Armed Forces of Ukraine is proposed on the basis of the stated views on the logistics theory of the Air Forces of the Armed Forces of Ukraine by assessing the set of real capabilities of each subsystem that is a part of its structure and system as a whole. At the same time, the assessment of the quality of the logistic support of the military units (formations) of the Air Forces of the Armed Forces of Ukraine should be related to the level of implementation of the potential capabilities of the logistics system when solving problems of each subsystem at the various stages of combat training, unblocking and operational deployment, the preparation and conduct of operations (combat actions), restoration of combat capability of troops (forces).
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Dalakoti, Vijay, Ravindra Bisht, R. P. Pant, and Mahesh Joshi. "A unified common fixed point theorem for a family of mappings." Filomat 35, no. 3 (2021): 759–69. http://dx.doi.org/10.2298/fil2103759d.
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The main objective of the paper is to prove some unified common fixed point theorems for a family of mappings under a minimal set of sufficient conditions. Our results subsume and improve a host of common fixed point theorems for contractive type mappings available in the literature of the metric fixed point theory. Simultaneously, we provide some new answers in a general framework to the problem posed by Rhoades (Contemp Math 72, 233-245, 1988) regarding the existence of a contractive definition which is strong enough to generate a fixed point, but which does not force the mapping to be continuous at the fixed point. Concrete examples are also given to illustrate the applicability of our proved results.
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Atteya, Ahmed. "Magnetic and Electrical Fields are not Invisible Fields but Real Mechanical Waves and vortices that shape throw Space Fabric Structure, Unified Theory of Gravity And Magnetism, The Physical Origin OF Lorentz Transformation." ICONTECH INTERNATIONAL JOURNAL 6, no. 1 (March 20, 2022): 7–25. http://dx.doi.org/10.46291/icontechvol6iss1pp7-25.
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One of the fundamental forces in nature is the electromagnetic force which is responsible for attraction and repulsion forces between charged particles, this force is consider until now invisible force and do not need medium shape in, I introduce this research for show new theory of electromagnetism and it flow throw space time fabric the same fabric gravity force shape throw, I will show in this research that all electromagnetic phenomena shape in the space time fabric structure and it is not invisible, we start that by prove new space time fabric physical property in interaction with matter that the fabric resist matter movement with speed in it with drag force, thus any accelerated particle will produce mechanical wave follow it in space time fabric.
Then we redefine space fabric from information in Alquran ALkareem and it is not vacuum but kind of structure that filled with matter but that matter is even and smooth without separation between its particles and atoms like ordinary matter and its real name is asmaa. according to concept that space fabric medium resist matter speed by drag force we will re understand electromagnetism phenomena.
Electron has very fast spinning movement in space fabric this will create circular wave in space fabric around electron as it resist matter speed, this wave is real mechanical wave that has force, if another electron get near the first their waves will make the two electrons move away from each other by wave pressure this called now repulsion force between electron or electrons has negative charge, we knew that atoms nucleus contain protons and neutrons and each contain three elementary particles called quarks, each quark has fast spin movement and will make circular wave around each one in space fabric, but quarks are close together by nuclear fore which is bigger than their waves repulsion force thus their waves will combined making big circular waves in space fabric around nucleus which known now as atom energy level or atoms orbits.
We will also show that magnetic fields are vortices or waves in space fabric that if we have direct current of electrons in wire all their circular electrons waves number will add together as electrons move similarly in same direction in wire make big circular real waves around wire in space fabric this is called now magnetic fields, and if we make this current of electron in wire alternative current, electron will move up and down making also their waves move up and down and due to space fabric physical properties this disturbance in space fabric will make transverse wave in space fabric structure moving away from wire with fixed speed depend on medium properties and this is called now electromagnetic waves, then found that Maxwell conclude his electromagnetic forces equation based on same final results of this research.
We will also illustrate special relativity experiment in concept that space fabric resist particles speed and the more object speed increase in space fabric the more its internal elections normal speed decrease not that speed of light is the ultimate speed and we will find drag force equation on particle or object accelerated in pace fabric , and from Maxwell equations we will find that drag force from space fabric to particles speed proportional to this factor which scientist Lorentz discover by pure numerical try and error .
We will also calculate space fabric drag force on electron moving in speed near light speed.
We also will know that the famous energy to mass relation come also from that drag force equation.
Finally we will apply our theory on light generation process and we will get new shape of light other than known today and that shape illustrate clearly why light has dual nature.
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Bowen, N. L. "The Electromagnetic Considerations of the Nuclear Force." Advanced Electromagnetics 6, no. 4 (November 14, 2017): 70–82. http://dx.doi.org/10.7716/aem.v6i4.665.
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This paper explores how the electromagnetic energies of the quarks within the nucleus affect the behavior of the nuclear force. By examining the electromagnetic energies and forces, many questions about nuclear behavior can be answered and many insights into the nucleus can be gained. Previous theoretical models for the nuclear force include only the Coulomb electric forces, but with a disregard of the electromagnetic characteristics of the quarks. By incorporating the electromagnetic energies and forces into nuclear theory, this model has been able to achieve predictions of binding energy better than any previous model, doing so by using only one variable instead of five. This model also directly unifies the nuclear force to the electromagnetic force.
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Mondal, Jagannath, Duncan Halverson, Isaac T. S. Li, Guillaume Stirnemann, Gilbert C. Walker, and Bruce J. Berne. "How osmolytes influence hydrophobic polymer conformations: A unified view from experiment and theory." Proceedings of the National Academy of Sciences 112, no. 30 (July 13, 2015): 9270–75. http://dx.doi.org/10.1073/pnas.1511780112.
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It is currently the consensus belief that protective osmolytes such as trimethylamine N-oxide (TMAO) favor protein folding by being excluded from the vicinity of a protein, whereas denaturing osmolytes such as urea lead to protein unfolding by strongly binding to the surface. Despite there being consensus on how TMAO and urea affect proteins as a whole, very little is known as to their effects on the individual mechanisms responsible for protein structure formation, especially hydrophobic association. In the present study, we use single-molecule atomic force microscopy and molecular dynamics simulations to investigate the effects of TMAO and urea on the unfolding of the hydrophobic homopolymer polystyrene. Incorporated with interfacial energy measurements, our results show that TMAO and urea act on polystyrene as a protectant and a denaturant, respectively, while complying with Tanford–Wyman preferential binding theory. We provide a molecular explanation suggesting that TMAO molecules have a greater thermodynamic binding affinity with the collapsed conformation of polystyrene than with the extended conformation, while the reverse is true for urea molecules. Results presented here from both experiment and simulation are in line with earlier predictions on a model Lennard–Jones polymer while also demonstrating the distinction in the mechanism of osmolyte action between protein and hydrophobic polymer. This marks, to our knowledge, the first experimental observation of TMAO-induced hydrophobic collapse in a ternary aqueous system.
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Hua, Jin, Lile He, Zhiqiang Kang, and Keding Yan. "A Force/Position Hybrid Controller for Rehabilitation Robot." INTERNATIONAL JOURNAL OF COMPUTERS COMMUNICATIONS & CONTROL 14, no. 5 (November 17, 2019): 615. http://dx.doi.org/10.15837/ijccc.2019.5.3651.
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The growing ageing population in China poses a huge demand for rehabilitation care, which can be satisfied by the latest robot technology. Focusing on the motion system of a six degrees-of-freedom (DOF) robot, this paper explores the relationship between the force, torque, velocity and the postures of the end effector and joint. Drawing on robot control theories, the existing manipulator force/position hybrid controllers were reviewed, and a force/position hybrid controller was designed for path planning of rehabilitation robot. Then, the robot was modelled on the Robot Operating System (ROS), using the Unified Robot Description Format (URDF) file and the MoveIt! Setup Assistant. Finally, our controller was tested in the ROS virtual simulation environment. The results show that our controller can facilitate and optimize the design of the path of rehabilitation robot.
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Loizu, J., and P. Helander. "Unified nonlinear theory of spontaneous and forced helical resonant MHD states." Physics of Plasmas 24, no. 4 (March 31, 2017): 040701. http://dx.doi.org/10.1063/1.4979678.
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Quan, Wu-yun, Dae M. Kim, and Myoung Kwan Cho. "Unified compact theory of tunneling gate current in metal–oxide–semiconductor structures: Quantum and image force barrier lowering." Journal of Applied Physics 92, no. 7 (October 2002): 3724–29. http://dx.doi.org/10.1063/1.1504173.
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Yim, Sung-Sam, and Young-Du Kwon. "A unified theory on solid-liquid separation: Filtration, expression, sedimentation, filtration by centrifugal force, and cross flow filtration." Korean Journal of Chemical Engineering 14, no. 5 (September 1997): 354–58. http://dx.doi.org/10.1007/bf02707051.
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Šorli, Amrit S., and Štefan Čelan. "Time-Invariant Superfluid Quantum Space as the Unified Field Theory." Reports in Advances of Physical Sciences 04, no. 03 (September 2020): 2050007. http://dx.doi.org/10.1142/s2424942420500073.
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The novelty of 21st-century physics is the development of the “superfluid quantum vacuum” model, also named “superfluid quantum space” that is replacing space-time as the fundamental arena of the universe. It also represents the model that has the potential of unifying four fundamental forces of the universe. Superfluid quantum space is represented as the time-invariant fundamental field of the universe where time is merely the duration of material changes.
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Wang, Ling, Bai Chen, Peng Wang, Sun Chen, Qian Yun Zhu, and Ya Juan Li. "Thrust Force Modeling of the Flagella-Like Swimming Micro-Robot." Applied Mechanics and Materials 461 (November 2013): 930–41. http://dx.doi.org/10.4028/www.scientific.net/amm.461.930.
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In this paper, helix tails with rectangular cross-section were designed for propelling a kind of flagella-like swimming robot. CFD (Computational Fluid Dynamics) software was applied to analyze the major influencing factors of the robots mechanical properties. It is revealed that the thrust reaches the maximum when the helix tails cross-section width is 0.36 times the diameter. Meanwhile, the helix tails should be designed according to the requirements with the largest diameter, close to but less than 45° helix angle and multi-turns under the limitation of the workspace. Combining these simulation data with the derivation process of Resistive Force Theory, the models for the mechanical properties simulation of the swimming robot were revised, and the explicit empirical formula of propulsive force is obtained. This model lays a good foundation for the robots motion control as well as unified mathematical description for macro-scale and micro-scale robots.
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Zhu, Xinhai, Klaus Weinmann, and Abhijit Chandra. "A Unified Bifurcation Analysis of Sheet Metal Forming Limits." Journal of Engineering Materials and Technology 123, no. 3 (February 7, 2001): 329–33. http://dx.doi.org/10.1115/1.1370397.
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The purpose of this study is to determine analytically the orientations of localized necks occurring in sheet metal forming processes, and obtain the corresponding forming limit diagrams (FLDs). In addition to the force equilibrium condition as adopted by other researchers, we include the moment equilibrium in this study. The shear terms due to the perturbation are found to vanish inside the localized neck of a region of deformation. This simplifies the two-dimensional problem to a one-dimensional problem. Furthermore, it is found that there are only three possible orientations for the initiation of a localized neck, i.e., two principal directions and one zero extension direction (which applies only to negative strain ratio deformations). A special case study using the von Mises yield criterion is also presented in this paper. Predictions from our unified analysis matches with the results of Hill, R., 1952, “On Discontinuous Plastic States, With Special Reference to Localized Necking in Thin Sheets,” J. Mech. Phys. Solids, 1, pp. 19–30. For the negative strain ratio regime (left-hand side of the FLDs), and with the results of Storen, S., and Rice, R., 1975, “Localized Necking in Thin Sheets,” J. Mech. Phys. Solids, 23, pp. 421–441. For the positive strain ratio regime (right hand-side of the FLD). When the localized neck is assumed to be in the zero extension direction for the negative strain ratio deformation, deformation theory and flow theory of plasticity give the same limit strains, and a unified solution to the limit strain is obtained. This solution is independent of the specific yield criterion used.
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Mariano, Paolo Maria. "Influence of the material substructure on crack propagation: a unified treatment." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 461, no. 2054 (February 8, 2005): 371–95. http://dx.doi.org/10.1098/rspa.2004.1392.
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The influence of the material texture (substructure) on the force driving the crack tip in complex materials is analysed in a three–dimensional continuum setting. The theory proposed accounts for finite deformations and general coarse–grained morphological descriptors of the substructure. A modified expression of the J integral is obtained together with other path integrals which are necessary to treat cases in which the process zone around the tip has finite size. They allow also us to consider the influence of the presence of diffused interfaces in multiphase solids on crack propagation. The results can be applied to a very wide class of material substructures occurring in condensed matter. To indicate possible applications, the behaviour of cracks in ferroelectrics and in materials with strain–gradient effects is discussed: the specializations of the general results reduce to expressions that fit reasonably experimental data.
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El-Shagi, Makram, Sebastian Giesen, and Logan J. Kelly. "THE QUANTITY THEORY REVISITED: A NEW STRUCTURAL APPROACH." Macroeconomic Dynamics 19, no. 1 (July 30, 2013): 58–78. http://dx.doi.org/10.1017/s1365100513000217.
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We propose a unified identification scheme to identify monetary shocks and track their propagation through the economy. We combine three approaches dealing with the consequences of monetary shocks. First, we adjust a state space version of the P-star type model employing money overhang as the driving force of inflation. Second, we identify the contemporaneous impact of monetary policy shocks by applying a sign restriction identification scheme to the reduced form given by the state space signal equations. Third, to ensure that our results are not distorted by the measurement error exhibited by the official monetary data, we employ the Divisia M4 monetary aggregate provided by the Center for Financial Stability. Our approach overcomes one of the major difficulties of previous models by using a data-driven identification of equilibrium velocity. Thus, we are able to show that a P-star model can fit U.S. data and money did indeed matter in the United States.