Variational Calculation of Lattice SU(N) Gauge System

A general method for an analytical calculation of SU(N)lattice gauge theories with finite N≥3 developed.As an example,the order parameter(E)of lattice SU(4)gauge systetn is calculated.The result is in good agree^nent with Monte Carlo simulations.

Research on the strain gauge mounting scheme of track wheel force measurement system based on high-speed wheel/rail relationship test rig

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.

An Expert System in Automatic Gauge Control for Rolling Process

Beacuse the practical mathematic model of rolling process can't be built accurately,this paper established an expert system to control the rolling steels' gauge by adjusting the setup roll open, which combined the experience of theoreticians and operators. The system applied the expression method of rule-skeleton+rule-body', and selected an appropriate non-exact reference model and self-study algorithm. The whole system, including auxiliary routes, is designed in Borland C++. Some experiments on this system have been done, and a good result has been achieved.

Higher resolution helium measuring system for deuterium plasma on EAST tokamak via normal Penning gauge

Although the deuterium and helium have almost the same mass,a Penning Optical Gas Analyzer（POGA） system on the basis of the spectroscopic method and Penning discharging has been designed on EAST,since 2014.The POGA system was developed successfully in 2015,it was the first time that EAST could detect helium partial pressure in deuterium plasma（wall conditioning and plasma operation scenario）.With dedicated calibration and proper adjustment of the parameters,the minimum concentration of helium in deuterium gas can be measured as about 0.5% instead of 1% on the other tokamak devices.Moreover,the He and D2 partial pressures are measured simultaneously.At present,the measurable range of deuterium partial pressure is 1×10^-7 mbar to 1×10^-5mbar,meanwhile the range of helium is 1×10^-8 mbar to 1×10^-5 mbar.The measurable range can be modified by means of the adjustment of POGA system＇s parameters.It is possible to detect the interesting part of the gas with a time resolution of less than 5 ms（the 200 ms because of conductance of transfer pipe at present）.The POGA system was routinely employed to wall conditioning and helium enrichment investigation in2015.Last but not the least,the low temperature plasma of POGA is generated by normal penning gauge Pfeiffer IKR gauge instead of Alcatel CF2 P,which has been suspended for a few years and was used for almost all the POGA systems in the world.

Strong Energy Condition of Simple Gauge Field System

An investigation is carried out for the violation of the strong energy condition by a generic field system consisting of charged scalar boson condensate,fermions,and U(1)gauge field.The Bose-Einstein condensation of the system is also studied by the Hamiltonian formulation.It is found that the strong energy condition can be violated by this quantum field system at high densities.

Gauge Conditions in the Singular Systems

In terms of the Dirac's finite contact transformation,we derive the principle on the choice of gauge conditions in the general singular Lagrangian system.It is applied successfully to Cawley's first counter-example of Dirac's conjecture.The number of gauge conditions or gauge freedoms is given and it is shown to be different from the accustomed conclusion which is always equal to the number of all the first-class constraints.

ON GAUGE EQUIVALENT INTEGRABLE SYSTEMS AND r_MATRICES FOR AKNS HIERARCHY AND A COUPLED MKdV HIERARCHY

The new coupled MKdV hierarchy is obtained. By using gauge transformation, the constrained flow, the integrable system and Lax representation for the coupled MKdV hierarchy were first constructed from the AKNS hierarchy and then using the Lax representation, the r_matrix for the constrained flow of the coupled MKdV hierarchy was constructed. The second set of conserved integrals of this constrained flow and their involutivity were also given.

Monitoring absolute vertical land motions and absolute sea-level changes from GPS and tide gauges data over French Polynesia

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.

Floquet engineering of a dynamical Z2 lattice gauge field with ultracold atoms

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.

Unification of Gravitational and Strong Interaction Fields Using Partial Gauge Symmetry

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.

Observation about the Classical Electromagnetic Gauge Transformation and Its Quantum Correspondence

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.

再谈“strain gauge”等若干名词术语的译意

为了进一步规范应变片技术的学术名词术语,现把常容易出错的一些学术用语的翻译和释义做一些介绍。并用相应的图示加以进一步说明,以供从事应变片、传感器技术研究及应用人员参考。

Gauge积分在HOL4中的形式化

积分是许多数学理论的基础,如实数分析、信号与系统中微分方程的求解等等。Gauge积分是黎曼积分在闭区间上的推广,应用更加方便。将Gauge积分的运算性质在HOL4(Higher-Order Logic 4)中形式化,包括积分的线性运算性质、积分不等式、分部积分、积分分裂定理、子区间的可积性、对特殊函数的积分的形式化及积分极限定理、柯西可积准则,并根据相关性质对反相积分器进行了验证。

关于Gauge积分的注记

在[1]中Armstrong和Lamoreaux定义了一种新型的积分,即Gauge积分和参导数 本文则证明了[1]中一些未证明的结论,并首次提出了Gauge积分的一些性质,对[1]作了一些补充;进一步,本文还系统讨论了Riemann,Lebesgue,Gauge三种积分之间的关系.

基于FusionWidgets Gauges开发高职院校人才培养工作状态数据仪表盘

提出使用FusionWidgets Gauges仪表盘套件展示高职院校人才培养工作状态数据量化指标的仪表盘方法,给出了实现原理,文末给出实现实例。

Evaluation of high-resolution satellite precipitation products with surface rain gauge observations from Laohahe Basin in northern China

Three high-resolution satellite precipitation products, the Tropical Rainfall Measuring Mission （TRMM） standard precipitation products 3B42V6 and 3B42RT and the Climate Precipitation Center＇s （CPC） morphing technique precipitation product （CMORPH）, were evaluated against surface rain gauge observations from the Laohahe Basin in northern China. Widely used statistical validation indices and categorical statistics were adopted. The evaluations were performed at multiple time scales, ranging from daily to yearly, for the years from 2003 to 2008. The results show that all three satellite precipitation products perform very well in detecting the occurrence of precipitation events, but there are some different biases in the amount of precipitation. 3B42V6, which has a bias of 21%, fits best with the surface rain gauge observations at both daily and monthly scales, while the biases of 3B42RT and CMORPH, with values of 81% and 67%, respectively, are much higher than a normal receivable threshold. The quality of the satellite precipitation products also shows monthly and yearly variation： 3B42RT has a large positive bias in the cold season from September to April, while CMORPH has a large positive bias in the warm season from May to August, and they all attained their best values in 2006 （with 10%, 50%, and -5% biases for 3B42V6, 3B42RT, and CMORPH, respectively）. Our evaluation shows that, for the Laohahe Basin, 3B42V6 has the best correspondence with the surface observations, and CMORPH performs much better than 3B42RT. The large errors of 3B42RT and CMORPH remind us of the need for new improvements to satellite precipitation retrieval algorithms or feasible bias adjusting methods.

Assimilated Tidal Results of Tide Gauge and TOPEX/POSEIDON Data over the China Seas Using a Variational Adjoint Approach with a Nonlinear Numerical Model

In order to obtain an accurate tide description in the China Seas, the 2-dimensional nonlinear numerical Princeton Ocean Model （POM） is employed to incorporate in situ tidal measurements both from tide gauges and TOPEX/POSEIDON （T/P） derived datasets by means of the variational adjoint approach in such a way that unknown internal model parameters, bottom topography, friction coefficients and open boundary conditions, for example, are adjusted during the process. The numerical model is used as a forward model. After the along-track T/P data are processed, two classical methods, i.e. harmonic and response analysis, are implemented to estimate the tide from such datasets with a domain covering the model area extending from 0° to 41°N in latitude and from 99°E to 142°E in longitude. And the results of these two methods are compared and interpreted. The numerical simulation is performed for 16 major constituents. In the data assimilation experiments, three types of unknown parameters （water depth, bottom friction and tidal open boundary conditions in the model equations） are chosen as control variables. Among the various types of data assimilation experiments, the calibration of water depth brings the most promising results. By comparing the results with selected tide gauge data, the average absolute errors are decreased from 7.9 cm to 6.8 cm for amplitude and from 13.0° to 9.0° for phase with respect to the semidiurnal tide M2 constituent, which is the largest tidal constituent in the model area. After the data assimilation experiment is performed, the comparison between model results and tide gauge observation for water levels shows that the RMS errors decrease by 9 cm for a total of 14 stations, mostly selected along the coast of China's Mainland, when a one-month period is considered, and the correlation coefficients improve for most tidal stations among these stations.

Clinical outcomes of 25-gauge vitrectomy surgery for vitreoretinal diseases: comparison of vitrectomy alone and phaco-vitrectomy

AIMTo compare the clinical outcomes of combined 25-gauge pars plana vitrectomy (PPV) and phacoemulsification/posterior chamber intraocular lens (PC-IOL) implantation with vitrectomy alone surgery in patients with various vitreoretinal diseases.METHODSA total of 306 eyes (145 with PPV alone and 161 with phaco-vitrectomy) were enrolled in this retrospective analysis. The surgical approach was 25-gauge PPV combined with phacoemulsification and PC-IOL implantation at the same time in eyes in phaco-vitrectomy group and only PPV in eyes in vitrectomy alone surgery group. The main outcome measures were postoperative clinical outcomes included anterior chamber inflammation, changes in intraocular pressure (IOP) and best corrected visual acuity (BCVA).RESULTSThe most common postoperative complication was anterior chamber reaction which has higher incidence in phaco-vitrectomy group (P<0.001). The mean postoperative 1st day IOP of vitrectomy alone group was significantly lower than that of phaco-vitrectomy group (16.3±5.8 mm Hg vs 17.8±8.1 mm Hg, respectively, P=0.02). Hypotony (IOP≤8 mm Hg) was not different between groups in the postoperative 1st day (P>0.05). The mean preoperative visual acuity was not different between groups (1.6±0.9 logMAR vs 1.8±0.9 logMAR, respectively, P>0.05). However, the mean visual acuity was decreased in vitrectomy alone group at the final visit compared to phaco-vitrectomy group (1.2±0.8 logMAR, 0.9±0.7 logMAR, respectively P<0.05).CONCLUSIONTwenty-five gauge PPV combined with phacoemulsification surgery is a safe and efficient procedure, which can be preferred in phacic patients with a variety of vitreoretinal diseases compared to vitrectomy alone. Despite improved outcomes, this approach is not free of limitations as anterior chamber complications especially with combined surgery.

Influence of band microstructure on carbide precipitation behavior and toughness of 1 GPa-grade ultra-heavy gauge low-alloy steel

This study investigated the influence of band microstructure induced by centerline segregation on carbide precipitation behavior and toughness in an 80 mm-thick 1 GPa low-carbon low-alloy steel plate.The quarter-thickness(1/4t)and half-thickness(1/2t)regions of the plate exhibited similar ductility and toughness after quenching.After tempering,the 1/4t region exhibited~50%and~25%enhancements in both the total elongation and low-temperature toughness at-40°C,respectively,without a decrease in yield strength,whereas the toughness of the 1/2t region decreased by~46%.After quenching,both the 1/4t and 1/2t regions exhibited lower bainite and lath martensite concentrations,but only the 1/2t region exhibited microstructure bands.Moreover,the tempered 1/4t region featured uniformly dispersed short rod-like M_(23)C_(6)carbides,and spherical MC precipitates with diameters of~20–100 nm and<20 nm,respectively.The uniformly dispersed nanosized M_(23)C_(6)carbides and MC precipitates contributed to the balance of high strength and high toughness.The band microstructure of the tempered 1/2t region featured a high density of large needle-like M3C carbides.The length and width of the large M3C carbides were~200–500 nm and~20–50 nm,respectively.Fractography analysis revealed that the high density of large carbides led to delamination cleavage fracture,which significantly deteriorated toughness.

Monitor automatic gauge control strategy with a Smith predictor for steel strip rolling

The simplified transfer function diagram block for a monitor automatic gauge control （Mon-AGC） system of strip steel rolling process was investigated. The new notion of strip sample length was given. In this way, the delay time varying with the rolling speed was evaded. After a Smith predictor was used to monitor the AGC system, the control laws were deduced for both proportional and integral regulators. The control strategies showed that by choosing the controller parameter P=∞ for both control algo- rithms each regulator could compensate the whole strip gage error in the first control step. The result shows that the integral algo- rithm is more controllable for the system regulating process and has a better steady-state precision than the proportional regulator. Compared with the traditional control strategy, the new control laws have a faster response speed and a hieher steadv-state precision.