Dynamic stability of axially accelerating viscoelastic plates with longitudinally varying tensions

The dynamic stability of axially accelerating plates is investigated. Longitudi- nally varying tensions due to the acceleration and nonhomogeneous boundary conditions are highlighted. A model of the plate combined with viscoelasticity is applied. In the viscoelastic constitutive relationship, the material derivative is used to take the place of the partial time derivative. Analytical and numerical methods are used to investigate summation and principal parametric resonances, respectively. By use of linear models for the transverse behavior in the small displacement regime, the plate is confined by a viscous damping force. The generalized Hamilton principle is used to derive the govern- ing equations, the initial conditions, and the boundary conditions of the coupled planar vibration. The solvability conditions are established by directly using the method of mul- tiple scales. The Routh-Hurwitz criterion is used to obtain the necessary and sufficient condition of the stability. Numerical examples are given to show the effects of related parameters on the stability boundaries. The validity of longitudinally varying tensions and nonhomogeneous boundary conditions is highlighted by comparing the results of the method of multiple scales with those of a differential quadrature scheme.

Analytical analysis for vibration of longitudinally moving plate submerged in infinite liquid domain

The vibration of a longitudinally moving rectangular plate submersed in an infinite liquid domain is studied analytically with the Rayleigh-Ritz method. The liquid is assumed to be incompressible, inviscid, and irrotational, and the velocity potential is used to describe the fluid velocity in the whole liquid field. The classical thin plate theory is used to derive mechanical energies of the traveling plate. As derivative of transverse displacement with respect to time in the compatibility condition equation exists, an exponential function is introduced to depict the dynamic deformation of the moving plate. It is shown that this exponential function works well with the Rayleigh- Ritz method. A convergence study shows a quick convergence speed for the immersed moving plate. Furthermore, the parametric study is carried out to demonstrate the effect of system parameters including the moving speed, the plate location, the liquid depth, the plate-liquid ratio, and the boundary condition. Results show that the above system parameters have significant influence on the vibration characteristics of the immersed moving plate. To extend the study, the method of added virtual mass incremental （AVMI） factor is used. The results show good agreement with those from the Rayleigh-Ritz method.

Correlation between serum uric acid levels and clinical characteristics in patients with longitudinally extensive transverse myelitis A case-control study

Uric acid is reduced in demyelinating diseases, including multiple sclerosis and neuromyelitis optica （NMO）. Longitudinally extensive transverse myelitis （LETM） is often an early manifestation of NMO. Whether uric acid levels are reduced at presentation of LETM remains unknown. The present study investigated serum uric acid levels by evaluating 35 patients with LETM, 64 with NMO, 62 with multiple sclerosis, 63 with other neurological diseases and 65 healthy controls. In addition, we tested the correlation between serum uric acid and the clinical characteristics of LETM. All patients were in the acute phase, defined as less than 1 month from onset or relapse. The results revealed that serum uric acid levels in LETM were significantly lower than in multiple sclerosis, other neurological diseases and healthy controls, but no difference was found between LETM and NMO. A negative correlation between uric acid levels and Expanded Disability Status Scale scores was found in LETM patients （r = -0.545, P 〈 0.05）. The results suggest that uric acid levels are reduced in patients with LETM, raising the possibility that lower uric acid levels are an indicator of disease disability. Moreover, reduced uric acid levels may be a risk factor in NMO.

Occasional Forces and Displacements of Longitudinally Coupled Ballastless Jointless Turnout on Bridges

For the longitudinally coupled baUastless turnout on Leida bridge on Wuhan-Guangzhou passenger dedicated line （PDL） in China, a turnout （cross over）-track slab-bridge deck-pier integrated finite element model was established, in which two No. 18 jointless turnouts with movable frogs in form of crossover, longitudinally coupled ballastless track, bridges and piers were regarded as one system. Based on this model, the additional forces and displacement regularities of turnouts, track slab, bridges and piers under occasional loading were analyzed, and the effect of occasional loading position was researched. The results show that slab breaking is more influential on the longitudinal force and deformation of the whole system than rail breaking, that slab breaking on one line could deteriorate both the slab force on another line and the forces exerted on the piers and fastener components, and that a great slab force at the left end of the continuous bridge expansion joint should be particularly avoided in design.

Analysis of the interaction between bolt-reinforced rock and surface support in tunnels based on convergence-confinement method

To investigate the interaction of the bolt-reinforced rock and the surface support,an analytical model of the convergence-confinement type is proposed,considering the sequential installation of the fully grouted rockbolts and the surface support.The rock mass is assumed to be elastic-brittle-plastic material,obeying the linear Mohr-Coulomb criterion or the non-linear Hoek-Brown criterion.According to the strain states of the tunnel wall at bolt and surface support installation and the relative magnitude between the bolt length and the plastic depth during the whole process,six cases are categorized upon solving the problem.Each case is divided into three stages due to the different effects of the active rockbolts and the passive surface support.The fictitious pressure is introduced to quantify the threedimensional(3D)effect of the tunnel face,and thus,the actual physical location along the tunnel axis of the analytical section can be considered.By using the bolt-rock strain compatibility and the rocksurface support displacement compatibility conditions,the solutions of longitudinal tunnel displacement and the reaction pressure of surface support along the tunnel axis are obtained.The proposed analytical solutions are validated by a series of 3D numerical simulations.Extensive parametric studies are conducted to examine the effect of the typical parameters of rockbolts and surface support on the tunnel displacement and the reaction pressure of the surface support under different rock conditions.The results show that the rockbolts are more effective in controlling the tunnel displacement than the surface support,which should be installed as soon as possible with a suitable length.For tunnels excavated in weak rocks or with restricted displacement control requirements,the surface support should also be installed or closed timely with a certain stiffness.The proposed method provides a convenient alternative approach for the optimization of rockbolts and surface support at the preliminary stage of tunnel design.

Super-resolution longitudinally polarized light needle achieved by tightly focusing radially polarized beams

Based on the vector diffraction theory, a super-resolution longitudinally polarized optical needle with ultra-long depth of focus(DOF) is generated by tightly focusing a radially polarized beam that is modulated by a self-designed ternary hybrid(phase/amplitude) filter(THF). Both the phase and the amplitude patterns of THF are judiciously optimized by the versatile particle swarm optimization(PSO) searching algorithm. For the focusing configuration with a combination of a high numerical aperture(NA) and the optimized sine-shaped THFs, an optical needle with the full width at half maximum(FWHM) of 0.414λ and the DOF of 7.58λ is accessed, which corresponds to an aspect ratio of 18.3. The demonstrated longitudinally polarized super-resolution light needle with high aspect ratio opens up broad applications in high-density optical data storage, nano-photolithography, super-resolution imaging and high-efficiency particle trapping.

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

Bunch-length measurement at a bunch-by-bunch rate based on time–frequency-domain joint analysis techniques and its application

This paper presents a new technique for measuring the bunch length of a high-energy electron beam at a bunch-by-bunch rate in storage rings.This technique uses the time–frequency-domain joint analysis of the bunch signal to obtain bunch-by-bunch and turn-by-turn longitudinal parameters,such as bunch length and synchronous phase.The bunch signal is obtained using a button electrode with a bandwidth of several gigahertz.The data acquisition device was a high-speed digital oscilloscope with a sampling rate of more than 10 GS/s,and the single-shot sampling data buffer covered thousands of turns.The bunch-length and synchronous phase information were extracted via offline calculations using Python scripts.The calibration coefficient of the system was determined using a commercial streak camera.Moreover,this technique was tested on two different storage rings and successfully captured various longitudinal transient processes during the harmonic cavity debugging process at the Shanghai Synchrotron Radiation Facility(SSRF),and longitudinal instabilities were observed during the single-bunch accumulation process at Hefei Light Source(HLS).For Gaussian-distribution bunches,the uncertainty of the bunch phase obtained using this technique was better than 0.2 ps,and the bunch-length uncertainty was better than 1 ps.The dynamic range exceeded 10 ms.This technology is a powerful and versatile beam diagnostic tool that can be conveniently deployed in high-energy electron storage rings.

Structural and functional connectivity of the whole brain and subnetworks in individuals with mild traumatic brain injury:predictors of patient prognosis

Patients with mild traumatic brain injury have a diverse clinical presentation,and the underlying pathophysiology remains poorly understood.Magnetic resonance imaging is a non-invasive technique that has been widely utilized to investigate neuro biological markers after mild traumatic brain injury.This approach has emerged as a promising tool for investigating the pathogenesis of mild traumatic brain injury.G raph theory is a quantitative method of analyzing complex networks that has been widely used to study changes in brain structure and function.However,most previous mild traumatic brain injury studies using graph theory have focused on specific populations,with limited exploration of simultaneous abnormalities in structural and functional connectivity.Given that mild traumatic brain injury is the most common type of traumatic brain injury encounte red in clinical practice,further investigation of the patient characteristics and evolution of structural and functional connectivity is critical.In the present study,we explored whether abnormal structural and functional connectivity in the acute phase could serve as indicators of longitudinal changes in imaging data and cognitive function in patients with mild traumatic brain injury.In this longitudinal study,we enrolled 46 patients with mild traumatic brain injury who were assessed within 2 wee ks of injury,as well as 36 healthy controls.Resting-state functional magnetic resonance imaging and diffusion-weighted imaging data were acquired for graph theoretical network analysis.In the acute phase,patients with mild traumatic brain injury demonstrated reduced structural connectivity in the dorsal attention network.More than 3 months of followup data revealed signs of recovery in structural and functional connectivity,as well as cognitive function,in 22 out of the 46 patients.Furthermore,better cognitive function was associated with more efficient networks.Finally,our data indicated that small-worldness in the acute stage could serve as a predictor of longitudinal changes in connectivity in patients with mild traumatic brain injury.These findings highlight the importance of integrating structural and functional connectivity in unde rstanding the occurrence and evolution of mild traumatic brain injury.Additionally,exploratory analysis based on subnetworks could serve a predictive function in the prognosis of patients with mild traumatic brain injury.

Longitudinal vibration characteristics of a tapered pipe pile considering the vertical support of surrounding soil and construction disturbance

This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile segment.The surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction disturbance.Then,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost zone.The displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent segment.Further,the displacement impedance at the pile head is obtained based on the impedance function transfer technique.Finally,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile.

Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform

This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary’s capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances.

Transverse mode-coupling instability with longitudinal impedance

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle loss.The mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were included.We performed computations for the circular electron-positron collider(CEPC)and observed a similar phenom-enon.Systematic studies on the influence of longitudinal impedance on the TMCI threshold were conducted.We concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI threshold.Additionally,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents

Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban settings.Despite this need,the longitudinal invariance of these measures over time remains understudied.This research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese teenagers.Method:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D assessment.After a three-month interval,967 of these participants repeated the CES-D evaluation.The study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural integrity.We investigated factorial invariance by conducting a twopronged CFA:one comparing urban vs.rural backgrounds,and another contrasting the results from the initial assessment with those from the follow-up.Results:The CES-D demonstrated adequate reliability in both rural and urban high school student samples.The preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected data.Invariance tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s invariance.Conclusions:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese adolescents.Its applicability is consistent across different living environments and remains stable over time.

Subclinical impairment of left ventricular myocardium function in type 2 diabetes mellitus patients with or without hypertension

BACKGROUND Cardiovascular disease has been the leading cause of morbidity and mortality for type 2 diabetes mellitus(T2DM)patients over the last decade.AIM To determine whether layer-specific global longitudinal strain(GLS)combined with peak strain dispersion(PSD)can be used to assess left ventricle(LV)myocardium systolic dysfunction in T2DM patients or without hypertension(HP).METHODS We enrolled 97 T2DM patients,70 T2DM+HP patients and 101 healthy subjects.Layer-specific GLS and PSD were calculated by EchoPAC software in apical three-,four-and two-chamber views.GLS of the epimyocardial,middle-layer and endomyocardial(GLSepi,GLSmid,and GLSendo)were measured and recorded.Receiver operating characteristic analysis was performed to detect LV myocardium systolic dysfunction in T2DM patients.RESULTS There were significant differences in GLSepi,GLSmid,GLSendo,and PSD between healthy subjects,T2DM patients and T2DM patients with HP(P<0.001).Trend tests yielded the ranking of healthy subjects>T2DM patients>T2DM with HP patients in the absolute values of GLSepi,GLSmid and GLSendo(P<0.001),while PSD was ranked healthy subjects<T2DM<T2DM with HP(P<0.001).Layer-specific GLS and PSD had high diagnostic efficiency for detecting LV myocardium systolic dysfunction in T2DM patients,however,the area under the curve(AUC)for layer-specific GLS and PSD combined was significantly higher than the AUCs for the individual indices(P<0.05).CONCLUSION Layer-specific GLS and PSD were associated with LV myocardium systolic dysfunction in T2DM patients,T2DM patients with HP.T2DM patients with HP have more severe LV myocardium systolic dysfunction than T2DM patients without HP and normal control patients.The combination of layer-specific GLS and PSD may provide additional prognostic information for T2DM patients with or without HP.

Evaluation of left ventricular systolic function in type 2 diabetes mellitus patients with and without peripheral vascular disease

BACKGROUND Peripheral vascular disease(PVD)is a common complication of type 2 diabetes mellitus(T2DM).Patients with T2DM have twice the risk of PVD as nondiabetic patients.AIM To evaluate left ventricular(LV)systolic function by layer-specific global longitudinal strain(GLS)and peak strain dispersion(PSD)in T2DM patients with and without PVD.METHODS Sixty-five T2DM patients without PVD,57 T2DM patients with PVD and 63 normal controls were enrolled in the study.Layer-specific GLS[GLS of the epimyocardium(GLSepi),GLS of the middle myocardium(GLSmid)and GLS of the endocardium(GLSendo)]and PSD were calculated.Receiver operating characteristic(ROC)analysis was performed to calculate the sensitivity and specificity of LV systolic dysfunction in T2DM patients with PVD.We calculated Pearson’s correlation coefficients between biochemical data,echocardiographic characteristics,and layer-specific GLS and PSD.RESULTS There were significant differences in GLSepi,GLSmid and GLSendo between normal controls,T2DM patients without PVD and T2DM patients with PVD(P<0.001).Trend tests revealed a ranking of normal controls>T2DM patients without PVD>T2DM patients with PVD in the absolute value of GLS(P<0.001).PSD differed significantly between the three groups,and the trend ranking was as follows:normal controls<T2DM patients without PVD<T2DM patients with PVD(P<0.001).ROC analysis revealed that the combination of layer-specific GLS and PSD had high diagnostic efficiency for detecting LV systolic dysfunction in T2DM patients with PVD.Lowdensity lipoprotein cholesterol was positively correlated with GLSepi,GLSmid and PSD(P<0.05),while LV ejection fraction was negatively correlated with GLSepi,GLSmid and GLSendo in T2DM patients with PVD(P<0.01).CONCLUSION PVD may aggravate the deterioration of LV systolic dysfunction in T2DM patients.Layer-specific GLS and PSD can be used to detect LV systolic dysfunction accurately and conveniently in T2DM patients with or without PVD.

Distribution Line Longitudinal ProtectionMethod Based on Virtual Measurement Current Restraint

As an effective approach to achieve the“dual-carbon”goal,the grid-connected capacity of renewable energy increases constantly.Photovoltaics are the most widely used renewable energy sources and have been applied on various occasions.However,the inherent randomness,intermittency,and weak support of grid-connected equipment not only cause changes in the original flow characteristics of the grid but also result in complex fault characteristics.Traditional overcurrent and differential protection methods cannot respond accurately due to the effects of unknown renewable energy sources.Therefore,a longitudinal protection method based on virtual measurement of current restraint is proposed in this paper.The positive sequence current data and the network parameters are used to calculate the virtual measurement current which compensates for the output current of photovoltaic(PV).The waveform difference between the virtual measured current and the terminal current for internal and external faults is used to construct the protection method.An improved edit distance algorithm is proposed to measure the similarity between virtual measurement current and terminal measurement current.Finally,the feasibility of the protection method is verified through PSCAD simulation.

Screening of Myocardial Cardiotoxicity Induced by Anticancer Chemotherapy and the Importance of Global Longitudinal Strain

Introduction: The improvement of survival in patients with cancer and the expansion of therapeutic options have led to the emergence of a new profile of cardiotoxicity, specifically associated with antimitotic agents. Our study aimed to assess the incidence of chemotherapy-induced myocardial toxicity in patients with cancer. Patients and Methods: We conducted a looking-forward longitudinal cohort study including all patients admitted to the Cardiology departments of Aristide le Dantec Hospital and Dalal Jamm National Hospital Centre for apre-chemotherapy check-up. The included patients did not undergo any pre-existing cardiopathy. Results: Over a period of two years ranging from January 2019 to December 2021, a total of 37 patients were included in the study. Notably, there was a female predominance (92%) with an average age of 49.7 years ± 13.69. Breast cancer accounted for 70% of the neoplasms. Laboratory findings revealed moderate anemia in 19 patients (51%). At inclusion, the left ventricle (LV) was of normal size (LV diastole at 44.46 ± 4.97 mm). The systolic function of the left ventricle was normal in all patients, with an average ejection fraction (EF) of 63.1% ± 5.80 and a mean global longitudinal strain (GLS) of −20.4% ± 2.58. The most commonly used agents were anthracyclines. During follow-up, 3 patients (8.1%) developed clinical symptoms of left heart failure, and LV dysfunction on echocardiography was observed in 5 (13.5%) patients, with a significant decrease in EF Conclusion: The incidence of cardiac toxicity is not negligible, hence the importance of early screening. Strain imaging is an essential tool that should be performed as part of the assessment before chemotherapy and re-evaluated during treatment.

Flexible pavement longitudinal joint quality evaluation using non-destructive testing

Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance.Current quality control(QC)and quality assurance(QA)plans provide limited coverage.Consequently,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation methods.It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics.The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality.The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint.The paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during construction.It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements.

Generation of structured light beams with polarization variation along arbitrary spatial trajectories using tri-layer metasurfaces

Conventionally,the spatially structured light beams produced by metasurfaces primarily highlight the polarization modulation of the beams propagating along the optical axis or the beams'spatial transmission trajectory.In particular,along the optical axis,the polarization state is either constant or varies continuously in each output plane.Here,we develop innovative spatially structured light beams with continually changing polarization along any arbitrary spatial transmission trajectories.With tri-layer metallic metasurfaces,the geometric characteristics of each layer structure can be adjusted to modulate the phase and polarization state of the incident terahertz(THz)wave.The beam will converge to the predefined trajectory along several paths to generate a Bessel-like beam with longitudinal polarization changes.We demonstrate the versatility of the approach by designing two THz-band structured light beams with varying polarization states along the spatial helical transmission trajectory.Continuous linear polarization changes and linear polarization to right circular polarization(RCP)and back to linear polarization changes are realized respectively.The experimental results are basically consistent with the simulated results.Our proposal for arbitrary trajectory structured light beams with longitudinally varying polarization offers a practical method for continuously regulating the characteristics of spatial structured light beams with non-axial transmission.This technique has potential uses in optical encryption,particle manipulation,and biomedical imaging.

Research on the Resistance of Cutting Mechanism of Mining Longitudinal Roadheader

In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analysis and derivation are carried out in detail.By using ADAMS to simulate,the resistance curve and torque curve of the cutting mechanism in different directions are obtained.The results show that ADAMS can effectively predict the excavation resistance and torque of the cutting mechanism of mining longitudinal roadheader,which has certain reference value for future optimization design.