In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining me...In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining method coupled with a temperature compensation strategy.To improve performance,a T-type device with a 1μm gap was fabricated resulting in an average sensitivity of 1.10 V/lgPa,which was 2.89 times larger than that(0.38 V/lgPa)of a L-type device with a 100μm gap.Additionally,FEA simulations were conducted,analyzing the influence of heater temperature on sensitivity and the attenuation of sensitivity across varying ambient temperatures.A semi-empirical theoretical mode was derived for performance prediction,demonstrating strong alignment with experimental results,underscoring its effectiveness in compensating for sensitivity attenuation.Building on the foundation,the device’s performance under different ambient temperatures was characterized and effectively compensated in two distinct operational modes:constant temperature mode and constant temperature difference mode(the whole range temperature compensation error can be controlled within 2.5%).Finally,the short-time stability(variation level is approximately 1 mV),noise floor(Vrms=384μV)and detection limit(0.07 Pa@1 Hz)of the device were characterized,confirming its suitability for practical implementation.展开更多
In this paper, in Section 1, we have described some equations and theorems concerning the Lebesgue integral and the Lebesgue measure. In Section 2, we have described the possible mathematical applications, of Lebesgue...In this paper, in Section 1, we have described some equations and theorems concerning the Lebesgue integral and the Lebesgue measure. In Section 2, we have described the possible mathematical applications, of Lebesgue integration, in some equations concerning various sectors of Chern-Simons theory and Yang-Mills gauge theory, precisely the two dimensional quantum Yang-Mills theory. In conclusion, in Section 3, we have described also the possible mathematical connections with some sectors of String Theory and Number Theory, principally with some equations concerning the Ramanujan’s modular equations that are related to the physical vibrations of the bosonic strings and of the superstrings, some Ramanujan’s identities concerning π and the zeta strings.展开更多
We have investigated the gauge dependence of physical observables in a quantum Rabi model under different potential fields arising from the Hilbert space truncation of the atomic degrees of freedom.In both the square-...We have investigated the gauge dependence of physical observables in a quantum Rabi model under different potential fields arising from the Hilbert space truncation of the atomic degrees of freedom.In both the square-well and harmonic potentials,the optimal gauge for the ground-state energy depends on the cavity frequency,which is optimal in the low-frequency limit,whereas the Coulomb gauge is optimal in the high-frequency limit.For a dynamic quantity,such as an out-of-time-order correlator,we have demonstrated the necessity of introducing an optimal dynamic gauge.This study provides deeper insight into the intricate relationship between gauge choice and the dynamics of quantum electrodynamics systems,resulting in more accurate theoretical frameworks.展开更多
Recently,a new method has been proposed to compute parton distributions using boosted correlators fixed in the Coulomb gauge(CG)within the framework of large-momentum effective theory.This approach,which does not invo...Recently,a new method has been proposed to compute parton distributions using boosted correlators fixed in the Coulomb gauge(CG)within the framework of large-momentum effective theory.This approach,which does not involve Wilson lines,could greatly improve the efficiency and precision of lattice quantum chromodynamics calculations.However,concerns remain regarding whether systematic uncertainties from Gribov copies,which correspond to ambiguities in lattice gauge-fixing,are adequately controlled.This work assesses the effects of Gribov copies on Coulomb-gauge-fixed quark correlators.We utilize different strategies for Coulomb-gauge fixing,selecting two different groups of Gribov copies based on lattice gauge configurations.We examine the differences in the resulting spatial quark correlators in both vacuum and pion states.Our findings indicate that the statistical errors of the matrix elements from both Gribov copies,regardless of the correlation range,decrease proportionally to the square root of the number of gauge configurations.The difference between the strategies does not show statistical significance compared to the gauge noise,demonstrating that the effect of the Gribov copies can be neglected in practical lattice calculations of quark parton distributions.展开更多
To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method w...To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was designed.Through simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was adopted.According to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and consistent.The standard error of the slope of the fitting equation of the downforce calculation model is 0.008.According to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,respectively.The coefficients of variation were 0.40,0.41,0.62,and 0.71,respectively.The results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting speed.Both the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.展开更多
In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as an...In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same locations.To verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good agreement.We obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/yr.The absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/yr.We discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.展开更多
Gauge field theory is a fundamental concept in modern physics,attracting many theoretical and experimental efforts towards its simulation.In this paper we propose that a simple model,in which fermions coupled to a dyn...Gauge field theory is a fundamental concept in modern physics,attracting many theoretical and experimental efforts towards its simulation.In this paper we propose that a simple model,in which fermions coupled to a dynamical lattice gauge field,can be engineered via the Floquet approach.The model possesses both an independent Maxwell term and local Z_(2) gauge symmetry.Our proposal relies on a species-dependent optical lattice,and can be achieved in one,two or three dimensions.By a unitary transformation,this model can be mapped into a non-interacting composite fermion system with fluctuating background charge.With the help of this composite fermion picture,two characteristic observations are predicted.One is radio-frequency spectroscopy,which exhibits no dispersion in all parameter regimes.The second is dynamical localization,which depends on the structure of the initial states.展开更多
Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/appro...Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/approach-Finite element method was employed to analyze the stress and strain distribution on the track wheel web surface under varying wheel-rail forces.Locations with minimal coupling interference between vertical and lateral forces were identified as suitable for strain gauge installation.Findings-The results show that due to the track wheel web’s unique curved shape and wheel-rail force loading mechanism,both tensile and compressive states exit on the surface of the web.When vertical force is applied,Mises stress and strain are relatively high near the inner radius of 710 mm and the outer radius of 1110mmof the web.Under lateral force,high Mises stress and strain are observed near the radius of 670mmon the inner and outer sides of the web.As the wheel-rail force application point shifts laterally toward the outer side,the Mises stress and strain near the inner radius of 710 mm of the web gradually decrease under vertical force while gradually increasing near the outer radius of 1110 mm of the web.Under lateral force,the Mises stress and strain on the surface of the web remain relatively unchanged regardless of the wheel-rail force application point.Based on the analysis of stress and strain on the surface of the web under different wheel-rail forces,the inner radius of 870 mm is recommended as the optimal mounting location of strain gauges for measuring vertical force,while the inner radius of 1143 mm is suitable for measuring lateral force.Originality/value-The research findings provide valuable insights for determining optimal strain gauge locations and designing an effective track wheel force measurement system.展开更多
We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms...We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms like the well-type potential where a particle behaves almost freely but is very hard to escape without external energy, which can be interpreted as local confinement and asymptotic freedom. By assuming a 2-dimensional metric tensor in 4-dimensional space-time, we suggest the existence of 3 kinds of particles that resemble QCD with 3 color charges. We also show that the mass term exists but comes to zero and derive the charge and spin values. We can regard the particle with this new potential as a gluon, and the interaction in this well-type potential as a strong interaction for the properties of mass, charge, spin, and its behavior. We suggest the eight-fold way with this new particle, which is similar to the existing method based on SU (3) symmetry. Even though the strong interaction has been analyzed in the standard model and string theory, we build a new consistent model based on the theory of relativity including Riemann geometry, and show the unification of gravitational and strong interactional field.展开更多
Objectives: As therapeutic modalities for rheumatoid arthritis (RA) advance, immediate and quantitative determination of RA disease status is becoming increasingly important. The purpose of this study was to validate ...Objectives: As therapeutic modalities for rheumatoid arthritis (RA) advance, immediate and quantitative determination of RA disease status is becoming increasingly important. The purpose of this study was to validate the usefulness of a ring gauge as a simple semiquantitative method for assessing hand swelling in patients with RA. Methods: We enrolled patients diagnosed with RA either initiated or switched to a biological therapeutic agent. The circumference of the interphalangeal (IP) joint and the proximal interphalangeal (PIP) joint was measured using a ring gauge. Assessments of the joint echocardiography, incorporating both Gray Scale (GS) and Power Doppler (PD) imaging, were conducted. These evaluations were performed both before the initiation of biological agent treatment and 28 days after the initial dose. Results: Following the treatment intervention, a significant reduction was observed in the circumference of the joint from the thumb to the little finger (p Conclusions: Our study demonstrated the effectiveness of using a ring gauge as a simple assessment tool for RA, revealing that a change in the ring gauge number by 2 or more corresponded to either improvement or deterioration in synovial thickening detected via joint echocardiography.展开更多
Using the Landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transform...Using the Landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.展开更多
A new mechanism for mass generation of gauge field is discussed in this paper. By introducing two sets of gauge fields and making the variations of these two sets of gauge fields compensated each other under local gau...A new mechanism for mass generation of gauge field is discussed in this paper. By introducing two sets of gauge fields and making the variations of these two sets of gauge fields compensated each other under local gauge transformations, the mass term of gauge fields is introduced into the Lagrangian without violating the local gauge symmetry of the Lagrangian. This model is a renormalizable quantum model.展开更多
With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions ...With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions may have different effects on the performance of the precipitation gauges, it is also necessary to test the gauges in different areas. This study mainly analyzed precipitation measurements from the single-Altershielded TRwS204 automatic weighing gauge(TRwS_(SA)) relative to the adjusted manual measurements(reference precipitation) from the Chinese standard precipitation gauge in a doublefence wind shield(CSPG_(DF)) in the Hulu watershed in the Qilian Mountains, China. The measurements were compared over the period from August 2014 to July2017, and the transfer function derived from the work by Kochendorfer et al.(2017 a) for correcting windinduced losses was applied to the TRwS_(SA) measurements. The results show that the average loss of TRwS_(SA) measurements relative to the reference precipitation decreased from 0.55 mm(10.7%) to 0.51 mm(9.9%) for rainfall events, from 0.35 mm(8.5%)to 0.22 mm(5.3%) for sleet events, and from 0.49 mm(18.9%) to 0.33 mm(12.7%) for snowfall events after adjustment. The uncorrected large biases of TRwS_(SA) measurements are considered to be mainly caused by specific errors of TRwS_(SA), different gauge orifice area and random errors. These types of errors must be considered when comparing precipitation measurements for different gauge types, especially in the mountains.展开更多
In order to provide manufacturers of carding machines and relevant accessories with theoretical references,how cylinder radius,setover and heel-toe difference affect cylinder-flat gauge of a carding machine was theore...In order to provide manufacturers of carding machines and relevant accessories with theoretical references,how cylinder radius,setover and heel-toe difference affect cylinder-flat gauge of a carding machine was theoretically studied.The relationship between cylinder-flat gauge and cylinder radius,setover and heel-toe difference was geometrically discussed.Numerical calculation and illustration about the relationship were made with MATLAB in accordance with practical settings.A general formula about the relationship is derived.A concept,the small-gauge zone length,has been defined for the first time,and some relevant results thus obtained.Given setover and heel-toe difference,the greater the cylinder radius,the greater the average gauge.If a smaller overall cylinder-flat gauge is desirable,it is not necessary to emphasize the tangential direction of the heel of clothed surface to the cylinder.Their intersection within a small zone is acceptable.In many cases,small-gauge zone can reduce average gauge which may be helpful to the carding action;given cylinder radius and setover,the smaller the heel-toe difference,the more helpful to reduce the overall gauge;given cylinder radius and heel-toe difference,the small-gauge zone length will increase with the increase of setover,so does the difference between the smallest gauge and outlet gauge.展开更多
We summarize our results about the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field with Landau’s gauge for the magnetic field, where Fourier’s transforma...We summarize our results about the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field with Landau’s gauge for the magnetic field, where Fourier’s transformation was used to analyze the problem, to point out that there exists a wave function which is different to that one given by Landau with the same Landau’s levels. The quantization of the magnetic flux is deduced differently to previous one, and a new solution is presented for the case of symmetric gauge of the magnetic field, and having the same Landau’s levels.展开更多
A new mechanism to introduce the mass of gauge field in supersymmetric gauge theory is discussed. The model has the strict local gauge symmetry and supersymmetry. Because we introduce two vector superfields simulta...A new mechanism to introduce the mass of gauge field in supersymmetric gauge theory is discussed. The model has the strict local gauge symmetry and supersymmetry. Because we introduce two vector superfields simultaneously, the model contains a massive gauge field as well as a massless gauge field.展开更多
In this paper, spinor and vector decompositions of SU（2） gauge potential are presented and their equivalence is constructed using a simply proposal. We also obtain the action of Faddeev nonlinear 0（3） sigma model ...In this paper, spinor and vector decompositions of SU（2） gauge potential are presented and their equivalence is constructed using a simply proposal. We also obtain the action of Faddeev nonlinear 0（3） sigma model from the SU（2） mass/ve gauge field theory, which is proposed according to the gauge invariant principle. At last, the knot structure in SU（2） Chern-Simons filed theory is discussed in terms of the Φ-mapping topological current theory, The topological charge of the knot is characterized by the Hopf indices and the Brouwer degrees of Φ-mapping.展开更多
Gauge potential plays an important role in exploring exotic phenomena in the single- and many-body quantum systems.In this paper,we propose a scheme to create both new Abelian and non-Abelian gauge potentials by adiab...Gauge potential plays an important role in exploring exotic phenomena in the single- and many-body quantum systems.In this paper,we propose a scheme to create both new Abelian and non-Abelian gauge potentials by adiabatically controlling the degenerate Dicke model in cavity quantum electrodynamics.It is shown that a non-Abelian gauge potential is achieved only for a single atom,whereas an Abelianizen diagonal gauge potential is realized for the atomic ensemble.More importantly,two interesting quantum phenomena such as the geometric phase and the magnetic monopole induced by our created gauge potentials are also predicted.The possible physical realization is presented in the macroscopic circuit quantum electrodynamics with the Cooper pair boxes,which act as the artificial two-level atoms controlled by the gate voltage and the external magnetic flux.展开更多
基金funded by the National Natural Science Foundation of China(62304023)partially funded by the National Key R&D Program of China(2023YFB3507300)+1 种基金Natural Science Foundation of Chongqing(2022NSCQ-MSX5423)Beijing Institute of Technology Research Fund Program for Young Scholars(XSQD-202206004).
文摘In this article,a CMOS-compatible Pirani vacuum gauge was proposed featuring enhanced sensitivity,lower detection limit,and high-temperature stability,achieved through the implementation of a surface micromachining method coupled with a temperature compensation strategy.To improve performance,a T-type device with a 1μm gap was fabricated resulting in an average sensitivity of 1.10 V/lgPa,which was 2.89 times larger than that(0.38 V/lgPa)of a L-type device with a 100μm gap.Additionally,FEA simulations were conducted,analyzing the influence of heater temperature on sensitivity and the attenuation of sensitivity across varying ambient temperatures.A semi-empirical theoretical mode was derived for performance prediction,demonstrating strong alignment with experimental results,underscoring its effectiveness in compensating for sensitivity attenuation.Building on the foundation,the device’s performance under different ambient temperatures was characterized and effectively compensated in two distinct operational modes:constant temperature mode and constant temperature difference mode(the whole range temperature compensation error can be controlled within 2.5%).Finally,the short-time stability(variation level is approximately 1 mV),noise floor(Vrms=384μV)and detection limit(0.07 Pa@1 Hz)of the device were characterized,confirming its suitability for practical implementation.
文摘In this paper, in Section 1, we have described some equations and theorems concerning the Lebesgue integral and the Lebesgue measure. In Section 2, we have described the possible mathematical applications, of Lebesgue integration, in some equations concerning various sectors of Chern-Simons theory and Yang-Mills gauge theory, precisely the two dimensional quantum Yang-Mills theory. In conclusion, in Section 3, we have described also the possible mathematical connections with some sectors of String Theory and Number Theory, principally with some equations concerning the Ramanujan’s modular equations that are related to the physical vibrations of the bosonic strings and of the superstrings, some Ramanujan’s identities concerning π and the zeta strings.
基金supported by the National Natural Science Foundation of China(Grant Nos.12174194 and 12475033)the Fundamental Research Funds for the Central Universities。
文摘We have investigated the gauge dependence of physical observables in a quantum Rabi model under different potential fields arising from the Hilbert space truncation of the atomic degrees of freedom.In both the square-well and harmonic potentials,the optimal gauge for the ground-state energy depends on the cavity frequency,which is optimal in the low-frequency limit,whereas the Coulomb gauge is optimal in the high-frequency limit.For a dynamic quantity,such as an out-of-time-order correlator,we have demonstrated the necessity of introducing an optimal dynamic gauge.This study provides deeper insight into the intricate relationship between gauge choice and the dynamics of quantum electrodynamics systems,resulting in more accurate theoretical frameworks.
基金supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics through Contract Nos. DE-AC02-06CH11357 and DE-SC0012704the frameworks of Scientific Discovery through Advanced Computing (SciDAC) award Fundamental Nuclear Physics at the Exascale and Beyond and the Quark-Gluon Tomography (QGT) Topical Collaboration, under contract No. DE-SC0023646partially supported by the 2023 Physical Sciences and Engineering (PSE) Early Investigator Named Award program at Argonne National Laboratory.
文摘Recently,a new method has been proposed to compute parton distributions using boosted correlators fixed in the Coulomb gauge(CG)within the framework of large-momentum effective theory.This approach,which does not involve Wilson lines,could greatly improve the efficiency and precision of lattice quantum chromodynamics calculations.However,concerns remain regarding whether systematic uncertainties from Gribov copies,which correspond to ambiguities in lattice gauge-fixing,are adequately controlled.This work assesses the effects of Gribov copies on Coulomb-gauge-fixed quark correlators.We utilize different strategies for Coulomb-gauge fixing,selecting two different groups of Gribov copies based on lattice gauge configurations.We examine the differences in the resulting spatial quark correlators in both vacuum and pion states.Our findings indicate that the statistical errors of the matrix elements from both Gribov copies,regardless of the correlation range,decrease proportionally to the square root of the number of gauge configurations.The difference between the strategies does not show statistical significance compared to the gauge noise,demonstrating that the effect of the Gribov copies can be neglected in practical lattice calculations of quark parton distributions.
基金supported by the State’s Key Project of Research and Development Plan of China(Grant No.2021YFD2000401)the Heilongjiang Province Engineering Science and Technology Major Project of China(Grant No.2020ZX17B01)the National Modern Agricultural Industry Technology System Project(Grant No.GARS-04).
文摘To effectively obtain the downforce of the gauge wheels in real time,mechanical models of the interaction among the ground,gauge wheels,gauge wheel arms,and depth adjustment lever were constructed.A measuring method was proposed for monitoring the downforce through a two-dimensional radial sensing device,and a corresponding prototype was designed.Through simulation analysis of the sensing device with ANSYS,a 45°angle was determined to exist between the strain gauge axis and the sensing device axis,and the Wheatstone bridging circuit of R1+R3−R5−R7(R stands for resistance strain gauge,different figures represent the strain gauge number)and R2+R4−R6−R8 was adopted.According to performance and calibration tests for the sensing device,the maximum interaction effect between the X and Y axes was 2.52%,and the output signal was stable and consistent.The standard error of the slope of the fitting equation of the downforce calculation model is 0.008.According to the field test,the average downforce of the gauge wheels was 1148,1017,843,and 713 N,at different sowing speeds of 6,8,10,and 12 km/h,respectively.The coefficients of variation were 0.40,0.41,0.62,and 0.71,respectively.The results indicate that the downforce fluctuation of the gauge wheels became more severe with increasing planting speed.Both the strain simulation analysis and field test verified that the measurement method is accurate and reliable,the performance of the sensing device is stable,the measurement method and sensing device meet the application requirements and lay a foundation for the research of accurate and stable control of downforce of no-till planter.
基金the University of French Polynesiafunding by several successive“Decision Aide a la Recherche”(DAR)grants to the Geodesy Observatory of Tahiti from the French Space Agency(CNES)+2 种基金fundings from the local government of French Polynesia(Observatoire Polynesien du Rechauffement Climatique)funding by“National Natural Science Foundation of China”(Grand No.41931075)funding by“the Fundamental Research Funds for the Central Universities"(Grand No.2042022kf1198)。
文摘In this study,we estimate the absolute vertical land motions at three tidal stations with collocated Global Navigation Satellite System(GNSS)receivers over French Polynesia during the period 2007-2020,and obtain,as ancillary results,estimates of the absolute changes in sea level at the same locations.To verify our processing approach to determining vertical motion,we first modeled vertical motion at the International GNSS Service(IGS)THTI station located in the capital island of Tahiti and compared our estimate with previous independent determinations,with a good agreement.We obtained the following estimates for the vertical land motions at the tide gauges:Tubuai island,Austral Archipelago-0.92±0.17 mm/yr,Vairao village,Tahiti Iti:-0.49±0.39 mm/yr,Rikitea,Gambier Archipelago-0.43±0.17 mm/yr.The absolute variations of the sea level are:Tubuai island,Austral Archipelago 5.25±0.60 mm/yr,Vairao village,Tahiti Iti:3.62±0.52 mm/yr,Rikitea,Gambier Archipelago 1.52±0.23 mm/yr.We discuss these absolute values in light of the values obtained from altimetric measurements and other means in French Polynesia.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.GG2030007011(WZ),GG203004045(WZ),12374477(PZ))Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302004(WZ))。
文摘Gauge field theory is a fundamental concept in modern physics,attracting many theoretical and experimental efforts towards its simulation.In this paper we propose that a simple model,in which fermions coupled to a dynamical lattice gauge field,can be engineered via the Floquet approach.The model possesses both an independent Maxwell term and local Z_(2) gauge symmetry.Our proposal relies on a species-dependent optical lattice,and can be achieved in one,two or three dimensions.By a unitary transformation,this model can be mapped into a non-interacting composite fermion system with fluctuating background charge.With the help of this composite fermion picture,two characteristic observations are predicted.One is radio-frequency spectroscopy,which exhibits no dispersion in all parameter regimes.The second is dynamical localization,which depends on the structure of the initial states.
基金funded by the Fund Project of China Academy of Railway Sciences Corporation Limited[Grant No.2022YJ194,2023YJ254].
文摘Purpose-This paper aims to analyze the stress and strain distribution on the track wheel web surface and study the optimal strain gauge location for force measurement system of the track wheel.Design/methodology/approach-Finite element method was employed to analyze the stress and strain distribution on the track wheel web surface under varying wheel-rail forces.Locations with minimal coupling interference between vertical and lateral forces were identified as suitable for strain gauge installation.Findings-The results show that due to the track wheel web’s unique curved shape and wheel-rail force loading mechanism,both tensile and compressive states exit on the surface of the web.When vertical force is applied,Mises stress and strain are relatively high near the inner radius of 710 mm and the outer radius of 1110mmof the web.Under lateral force,high Mises stress and strain are observed near the radius of 670mmon the inner and outer sides of the web.As the wheel-rail force application point shifts laterally toward the outer side,the Mises stress and strain near the inner radius of 710 mm of the web gradually decrease under vertical force while gradually increasing near the outer radius of 1110 mm of the web.Under lateral force,the Mises stress and strain on the surface of the web remain relatively unchanged regardless of the wheel-rail force application point.Based on the analysis of stress and strain on the surface of the web under different wheel-rail forces,the inner radius of 870 mm is recommended as the optimal mounting location of strain gauges for measuring vertical force,while the inner radius of 1143 mm is suitable for measuring lateral force.Originality/value-The research findings provide valuable insights for determining optimal strain gauge locations and designing an effective track wheel force measurement system.
文摘We propose the new field potential by maintaining both the symmetry of the scalar gauge and the conservation law keeping N?ether’s theorem, while disregarding the symmetry of the vector gauge. The new potential forms like the well-type potential where a particle behaves almost freely but is very hard to escape without external energy, which can be interpreted as local confinement and asymptotic freedom. By assuming a 2-dimensional metric tensor in 4-dimensional space-time, we suggest the existence of 3 kinds of particles that resemble QCD with 3 color charges. We also show that the mass term exists but comes to zero and derive the charge and spin values. We can regard the particle with this new potential as a gluon, and the interaction in this well-type potential as a strong interaction for the properties of mass, charge, spin, and its behavior. We suggest the eight-fold way with this new particle, which is similar to the existing method based on SU (3) symmetry. Even though the strong interaction has been analyzed in the standard model and string theory, we build a new consistent model based on the theory of relativity including Riemann geometry, and show the unification of gravitational and strong interactional field.
文摘Objectives: As therapeutic modalities for rheumatoid arthritis (RA) advance, immediate and quantitative determination of RA disease status is becoming increasingly important. The purpose of this study was to validate the usefulness of a ring gauge as a simple semiquantitative method for assessing hand swelling in patients with RA. Methods: We enrolled patients diagnosed with RA either initiated or switched to a biological therapeutic agent. The circumference of the interphalangeal (IP) joint and the proximal interphalangeal (PIP) joint was measured using a ring gauge. Assessments of the joint echocardiography, incorporating both Gray Scale (GS) and Power Doppler (PD) imaging, were conducted. These evaluations were performed both before the initiation of biological agent treatment and 28 days after the initial dose. Results: Following the treatment intervention, a significant reduction was observed in the circumference of the joint from the thumb to the little finger (p Conclusions: Our study demonstrated the effectiveness of using a ring gauge as a simple assessment tool for RA, revealing that a change in the ring gauge number by 2 or more corresponded to either improvement or deterioration in synovial thickening detected via joint echocardiography.
文摘Using the Landau and symmetric gauges for the vector potential of a constant magnetic field and the quantum problem of a charged particle moving on a flat surface, we show the classical electromagnetic gauge transformation does not correspond to a one-dimensional unitary group transformation U(1) of the wave function for the quantum case. In addition, with the re-examination of the relation between the magnetic field B and its vector potential A, we found that, in order to have a consistent formulation of the dynamics of the charged particle with both expressions, we must have that B=∇×A if and only if B≠0.
文摘A new mechanism for mass generation of gauge field is discussed in this paper. By introducing two sets of gauge fields and making the variations of these two sets of gauge fields compensated each other under local gauge transformations, the mass term of gauge fields is introduced into the Lagrangian without violating the local gauge symmetry of the Lagrangian. This model is a renormalizable quantum model.
基金supported primarily by the National Basic Research Program of China (2013CBA01806)the National Natural Sciences Foundation of China (41671029, 41690141, 41401040 and 41501040)
文摘With the popularity of the automatic precipitation gauges in national weather stations,testing their performance and adjusting their measurements are top priorities. Additionally,because different climatic conditions may have different effects on the performance of the precipitation gauges, it is also necessary to test the gauges in different areas. This study mainly analyzed precipitation measurements from the single-Altershielded TRwS204 automatic weighing gauge(TRwS_(SA)) relative to the adjusted manual measurements(reference precipitation) from the Chinese standard precipitation gauge in a doublefence wind shield(CSPG_(DF)) in the Hulu watershed in the Qilian Mountains, China. The measurements were compared over the period from August 2014 to July2017, and the transfer function derived from the work by Kochendorfer et al.(2017 a) for correcting windinduced losses was applied to the TRwS_(SA) measurements. The results show that the average loss of TRwS_(SA) measurements relative to the reference precipitation decreased from 0.55 mm(10.7%) to 0.51 mm(9.9%) for rainfall events, from 0.35 mm(8.5%)to 0.22 mm(5.3%) for sleet events, and from 0.49 mm(18.9%) to 0.33 mm(12.7%) for snowfall events after adjustment. The uncorrected large biases of TRwS_(SA) measurements are considered to be mainly caused by specific errors of TRwS_(SA), different gauge orifice area and random errors. These types of errors must be considered when comparing precipitation measurements for different gauge types, especially in the mountains.
基金Fund of Scientific and Technological Key Project Plan of Liaoning Province,China (No2003220026)
文摘In order to provide manufacturers of carding machines and relevant accessories with theoretical references,how cylinder radius,setover and heel-toe difference affect cylinder-flat gauge of a carding machine was theoretically studied.The relationship between cylinder-flat gauge and cylinder radius,setover and heel-toe difference was geometrically discussed.Numerical calculation and illustration about the relationship were made with MATLAB in accordance with practical settings.A general formula about the relationship is derived.A concept,the small-gauge zone length,has been defined for the first time,and some relevant results thus obtained.Given setover and heel-toe difference,the greater the cylinder radius,the greater the average gauge.If a smaller overall cylinder-flat gauge is desirable,it is not necessary to emphasize the tangential direction of the heel of clothed surface to the cylinder.Their intersection within a small zone is acceptable.In many cases,small-gauge zone can reduce average gauge which may be helpful to the carding action;given cylinder radius and setover,the smaller the heel-toe difference,the more helpful to reduce the overall gauge;given cylinder radius and heel-toe difference,the small-gauge zone length will increase with the increase of setover,so does the difference between the smallest gauge and outlet gauge.
文摘We summarize our results about the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field with Landau’s gauge for the magnetic field, where Fourier’s transformation was used to analyze the problem, to point out that there exists a wave function which is different to that one given by Landau with the same Landau’s levels. The quantization of the magnetic flux is deduced differently to previous one, and a new solution is presented for the case of symmetric gauge of the magnetic field, and having the same Landau’s levels.
文摘A new mechanism to introduce the mass of gauge field in supersymmetric gauge theory is discussed. The model has the strict local gauge symmetry and supersymmetry. Because we introduce two vector superfields simultaneously, the model contains a massive gauge field as well as a massless gauge field.
基金＊The project supported by National Natural Science Foundation of China and the Doctoral Foundation of the Ministry of Education of China
文摘In this paper, spinor and vector decompositions of SU（2） gauge potential are presented and their equivalence is constructed using a simply proposal. We also obtain the action of Faddeev nonlinear 0（3） sigma model from the SU（2） mass/ve gauge field theory, which is proposed according to the gauge invariant principle. At last, the knot structure in SU（2） Chern-Simons filed theory is discussed in terms of the Φ-mapping topological current theory, The topological charge of the knot is characterized by the Hopf indices and the Brouwer degrees of Φ-mapping.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10904092,10934004,60978018,11074184,and 11074154the Zhejiang Provincial Natural Science Foundation under Grant No.Y6090001
文摘Gauge potential plays an important role in exploring exotic phenomena in the single- and many-body quantum systems.In this paper,we propose a scheme to create both new Abelian and non-Abelian gauge potentials by adiabatically controlling the degenerate Dicke model in cavity quantum electrodynamics.It is shown that a non-Abelian gauge potential is achieved only for a single atom,whereas an Abelianizen diagonal gauge potential is realized for the atomic ensemble.More importantly,two interesting quantum phenomena such as the geometric phase and the magnetic monopole induced by our created gauge potentials are also predicted.The possible physical realization is presented in the macroscopic circuit quantum electrodynamics with the Cooper pair boxes,which act as the artificial two-level atoms controlled by the gate voltage and the external magnetic flux.
