Effects of shore-normal coastal structure on medium-to long-term embayed shoreline evolution

Based on high-tide shoreline data extracted from 87 Landsat satellite images from 1986 to 2019 as well as using the linear regression rate and performing a Mann-Kendall(M–K)trend test,this study analyzes the linear characteristics and nonlinear behavior of the medium-to long-term shoreline evolution of Jinghai Bay,eastern Guangdong Province.In particular,shoreline rotation caused by a shore-normal coastal structure is emphasized.The results show that the overall shoreline evolution over the past 30 years is characterized by erosion on the southwest beach,with an average erosion rate of 3.1 m/a,and significant accretion on the northeast beach,with an average accretion rate of 5.6 m/a.Results of the M–K trend test indicate that significant shoreline changes occurred in early 2006,which can be attributed to shore-normal engineering.Prior to that engineering construction,the shorelines are slightly eroded,where the average erosion rate is 0.7 m/a.However,after shore-normal engineering is performed,the shoreline is characterized by significant erosion(3.2 m/a)on the southwest beach and significant accretion(8.5 m/a)on the northeast beach,thus indicating that the shore-normal engineering at the updrift headland contributes to clockwise shoreline rotation.Further analysis shows that the clockwise shoreline rotation is promoted not only by longshore sediment transport processes from southwest to northeast,but also by cross-shore sediment transport processes.These findings are crucial for beach erosion risk management,coastal disaster zoning,regional sediment budget assessments,and further observations and predictions of beach morphodynamics.

THE THEORY AND APPLICATION OF THE STRUCTURE LIGHT ENGINEERING SURVEYING BASED ON A LASER THEODOLITE WITH THREE FREEDOMS OF ROTATION

The concepts of “confining structure” and structure light are illuminated in this paper.A laser theodolite with three freedoms of rotation,which is aimed at “confining structure”,is developed.Various scanning modes and their mathematical models based on laser theodolite with three freedoms of rotation are discussed.According to the features of a huge object,,the structure light engineering surveying based on laser theodolite with three freedoms of rotation is determined as the main method in an actual application.The observation of four sound concrete posts and forced centering plates.Subsequently,it is transformed into the huge object coordinate system.The scanning mode with plumb plane is selected as the main mode in the whole work.And other assistant methods,such as close range photogrammetry and the method of using reflection sheet,are applied to the work of “scanning dead angle”.At last,a surveying accuracy estimation of this method is done and a surveying accuracy test is finished.It can be concluded that the structure light engineering surveying based on laser theodolite with three freedoms of rotation is considered to be an effective and applied method,and has many superiority to some other surveying methods in the work of surveying “confining structure”.

Liquid-solid mass transfer in a rotating packed bed reactor with structured foam packing

A rotating packed bed(RPB) reactor has substantially potential for the process intensification of heterogeneous catalytic reactions. However, the scarce knowledge of the liquid–solid mass transfer in the RPB reactor is a barrier for its design and scale-up. In this work, the liquid–solid mass transfer in a RPB reactor installed with structured foam packing was experimentally studied using copper dissolution by potassium dichromate. Effects of rotational speed, liquid and gas volumetric flow rate on the liquid–solid mass transfer coefficient(kLS) have been investigated. The correlation for predicting kLSwas proposed, and the deviation between the experimental and predicted values was within±12%. The liquid–solid volumetric mass transfer coefficient(kLSaLS) ranged from 0.04–0.14 1^-1, which was approximately 5 times larger than that in the packed bed reactor. This work lays the foundation for modeling of the RPB reactor packed with structured foam packing for heterogeneous catalytic reaction.

A 3-Node Co-Rotational Triangular Finite Element for Non-Smooth,Folded and Multi-Shell Laminated Composite Structures

Based on the first-order shear deformation theory,a 3-node co-rotational triangular finite element formulation is developed for large deformation modeling of non-smooth,folded and multi-shell laminated composite structures.The two smaller components of the mid-surface normal vector of shell at a node are defined as nodal rotational variables in the co-rotational local coordinate system.In the global coordinate system,two smaller components of one vector,together with the smallest or second smallest component of another vector,of an orthogonal triad at a node on a non-smooth intersection of plates and/or shells are defined as rotational variables,whereas the two smaller components of the mid-surface normal vector at a node on the smooth part of the plate or shell(away from non-smooth intersections)are defined as rotational variables.All these vectorial rotational variables can be updated in an additive manner during an incremental solution procedure,and thus improve the computational efficiency in the nonlinear solution of these composite shell structures.Due to the commutativity of all nodal variables in calculating of the second derivatives of the local nodal variables with respect to global nodal variables,and the second derivatives of the strain energy functional with respect to local nodal variables,symmetric tangent stiffness matrices in local and global coordinate systems are obtained.To overcome shear locking,the assumed transverse shear strains obtained from the line-integration approach are employed.The reliability and computational accuracy of the present 3-node triangular shell finite element are verified through modeling two patch tests,several smooth and non-smooth laminated composite shells undergoing large displacements and large rotations.

Preheating-assisted solid-state friction stir repair of Al-Mg-Si alloy plate at different rotational speeds

Additive friction stir deposition(AFSD)is a novel structural repair and manufacturing technology has become a research hotspot at home and abroad in the past five years.In this work,the microstructural evolution and mechanical performance of the Al-Mg-Si alloy plate repaired by the preheating-assisted AFSD process were investigated.To evaluate the tool rotation speed and substrate preheating for repair quality,the AFSD technique was used to additively repair 5 mm depth blind holes on 6061 aluminum alloy substrates.The results showed that preheat-assisted AFSD repair significantly improved joint bonding and joint strength compared to the control non-preheat substrate condition.Moreover,increasing rotation speed was also beneficial to improve the metallurgical bonding of the interface and avoid volume defects.Under preheating conditions,the UTS and elongation were positively correlated with rotation speed.Under the process parameters of preheated substrate and tool rotation speed of 1000 r/min,defect-free specimens could be obtained accompanied by tensile fracture occurring in the substrate rather than the repaired zone.The UTS and elongation reached the maximum values of 164.2MPa and 13.4%,which are equivalent to 99.4%and 140%of the heated substrate,respectively.

Effect of passive structure and toroidal rotation on resistive wall mode stability in the EAST tokamak

If βN exceeds βNno-wall, the plasma will be unstable because of external kink and resistive wall mode （RWM）. In this article, the effect of the passive structure and the toroidal rotation on the RWM stability in the experimental advanced superconducting tokamak （EAST） are simulated with CHEASE and MARS codes. A model using a one-dimensional （1D） surface to present the effect of the passive plate is proved to be credible. The no wall fiN limit is about 3li, and the ideal wall βN limit is about 4.5li on EAST. It is found that the rotation near the q = 2 surface and the plasma edge affects the RWM more.

ALGEBRAIC STRUCTURES AND POISSON INTEGRALS OF RELATIVISTIC DYNAMICAL EQUATIONS FOR ROTATIONALSYSTEMS

The algebraic structures of the dynamical equations for the rotational relativistic systems are studied. It is found that the dynamical equations of holonomic conservative rotational relativistic systems and the special nonholonomic rotational relativistic systems have Lie's algebraic structure, and the dynamical equations of the general holonomic rotational relativistic systems and the general nonholonomic rotational relativistic systems have Lie admitted algebraic structure. At last the Poisson integrals of the dynamical equations for the rotational relativistic systems are given.

The Effect of Spectral Index Parameter κ on Obliquely Propagating Solitary Wave Structures in Magneto-Rotating Plasmas

Nonlinear ion-acoustic solitary wave structures in collisionless,non-relativistic,homogenous,magneto-rotating plasma,in which the electron species follow the kappa distribution function,are studied.The Korteweg-de Vries (KdV) equation is derived by using the reductive perturbation method,and the effects of different plasma parameters on the obliquely propagating nonlinear solitary wave structures in the magneto-rotating plasma are presented.It is noticed that the spectral index parameter κ significantly modifies the nonlinear wave structure.

Seismic response of large-span spatial structures under multi-support and multidimensional excitations including rotational components

To achieve rational and precise seismic response predictions of large span spatial structures(LSSSs),the inherent non-uniformity and multidimensionality characteristics of earthquake ground motions should be properly taken into consideration.However,due to the limitations of available earthquake stations to record seismic rotational components,the effects of rocking and torsional earthquake components are commonly neglected in the seismic analyses of LSSSs.In this study,a newly developed method to extract the rocking and torsion components at any point along the area of a deployed dense array from the translational earthquake recordings is applied to obtain the rotational seismic inputs for a LSSS.The numerical model of an actual LSSS,the Dalian International Conference Center(DICC),is developed to study the influences of multi-support and multidimensional excitations on the seismic responses of LSSSs.The numerical results reveal that the non-uniformity and multidimensionality of ground motion input can considerably affect the dynamic response of the DICC.The specific degree of influence on the overall and local structural displacements,deformations and forces are comprehensively investigated and discussed.

Rotational Spectra and Molecular Structures of Ethylanilines

The molecular structures of three ethylanilines,ortho-,meta-and para-ethylaniline,have been obtained by means of Fourier-transform microwave spectroscopy.Rotational spectra of all three molecules display the nuclear quadrupole hyperfine structures arising from the 14N nucleus.Comparison of the determined structures allows a direct study of the influence of the position of the ethyl substituent on the structure of the amino group communicated through the phenyl ring.

Electric-field-induced in-plane effective 90°magnetization rotation in Co2FeAl/PMN-PT structure

The in-plane effective 90°magnetization rotation of Co_(2) FeAl thin film grown on PMN-PT substrate induced by the electric field is investigated at room temperature.The magnetic hysteresis loops under different positive and negative electric fields are obtained,which reveals remanent magnetization can be mediated by the electric field.Moreover,under positive electric fields,the obvious 90°magnetization rotation can be observed,while remanent magnetization is nearly unchanged under negative electric fields.The result is consistent with the electric field dependence of effective magnetic field,which can be attributed to the piezostrain effect in Co_(2) FeAl/PMN-PT structure.In addition,the piezostrain-mediated 90°magnetization rotation can be demonstrated by the result of resonance field changing with electric field in the measurement of ferromagnetic resonance,which is promising for the design of future multiferroic devices.

Dynamic Balancing Structure Optimal Design for the Rotating Arc Sensor

Rotating arc sensor is a key device for automation welding. The vibration has a big influence on signal's correct collection and reliable automatic welding. In order to solve the vibration problem and the dynamic balancing design with the restricted space,a bearing force analysis based dynamic balancing structure optimal design is proposed and implemented with the help of Pro/Engineer( PROE) and automatic dynamic analysis of mechanical systems( ADAMS) virtual prototype technology, in which three parameters of the counterbalance are considered. The method is suitable for the practical online adjustment. The simulation result shows that optimal design based counterbalance structure and parameters can satisfy the space requirement with lower vibration. The methodology provides a new idea for dynamic balancing design and adjustment of rotating arc sensor with adjustable rotation radius.

Impact of Crop Rotation on Pathotype and Genetic Structure of Phythophthora sojae in Fields

To estimate the impact of crop rotation on the pathotype and genetic structure of Phythophthora sojae in fields, 372 isolates of P. sojae were obtained from long-term localisation experimental fields in Heilongjiang Province of China. The hypocotyl inoculation method was used to characterize the virulence of P. sojae on 13 differential cultivars, and the amplified fragment length polymorphism（AFLP） technique was used to analyze difference in the genetic structure of P. sojae. The results indicated that an abundant diversity of genetic structures and pathotypes of P. sojae, a more uniform distribution of pathotypes and less dominance of pathotypes occurred in corn-soybean and wheat-soybean rotation fields than in a continuous soybean mono-cropping field. These findings suggested that P. sojae did not easily become the dominant race in rotation fields, which maintain disease resistance in soybean varieties. Therefore, the results of this study suggested that Phytophthora stem and root rot of soybeans could be effectively controlled by rotating soybeans with non-host crops of corn and wheat.

A comprehensive analysis of the response of the fungal community structure to long-term continuous cropping in three typical upland crops

Certain agricultural management practices are known to affect the soil microbial community structure;however,knowledge of the response of the fungal community structure to the long-term continuous cropping and rotation of soybean,maize and wheat in the same agroecosystem is limited.We assessed the fungal abundance,composition and diversity among soybean rotation,maize rotation and wheat rotation systems and among long-term continuous cropping systems of soybean,maize and wheat as the effect of crop types on fungal community structure.We compared these fungal parameters of same crop between long-term crop rotation and continuous cropping systems as the effect of cropping systems on fungal community structure.The fungal abundance and composition were measured by quantitative real-time PCR and Illumina MiSeq sequencing.The results revealed that long-term continuous soybean cropping increased the soil fungal abundance compared with soybean rotation,and the fungal abundance was decreased in long-term continuous maize cropping compared with maize rotation.The long-term continuous soybean cropping also exhibited increased soil fungal diversity.The variation in the fungal community structure among the three crops was greater than that between long-term continuous cropping and rotation cropping.Mortierella,Guehomyces and Alternaria were the most important contributors to the dissimilarity of the fungal communities between the continuous cropping and rotation cropping of soybean,maize and wheat.There were 11 potential pathogen and 11 potential biocontrol fungi identified,and the relative abundance of most of the potential pathogenic fungi increased during the long-term continuous cropping of all three crops.The relative abundance of most biocontrol fungi increased in long-term continuous soybean cropping but decreased in long-term continuous maize and wheat cropping.Our results indicate that the response of the soil fungal community structure to long-term continuous cropping varies based upon crop types.

STUDY ON SENSITIVITY OF WIND FIELD VARIATION TO STRUCTURE AND DEVELOPMENT OF CONVECTIVE STORMS

In order to study the impacts of wind field variations in the middle and lower troposphere on the development and structure of storms,we carried out numerical experiments on cases of severe convection in the Jianghuai area under the background of cold vortex on April 28,2015.The results show that the structure and development of convective storms are highly sensitive to the changes of wind fields,and the adjustment of wind fields in the middle or lower troposphere will lead to significant changes in the development and structure of storms.When the wind field in the middle or lower troposphere is weakened,the development of convective storms attenuates to some extent compared with that in the control experiment,and the ways of attenuation in the two experiments are different.In the attenuation test of wind field at the middle level,convective storms obviously weaken at all stages in its development,while for the wind field at the low level,the convective storms weaken only in the initial stage of storm.On the contrary,the enhancement of the wind field in the middle or lower troposphere is conducive to the development of convection,especially the enhancement in the middle troposphere.In contrast,the convective storms develop rapidly in this test,as the most intensive one.The wind field variations have significant impacts on the structure and organization of the storm.The enhancement of wind field in the middle troposphere facilitates the intension of the middle-level rotation in convective storm,the reduction of the storm scale,and the organized evolution of convective storms.The strengthening of the wind field in the lower troposphere is conducive to the development of the low-level secondary circulation of the storm and the cyclonic vorticity at the middle and low levels on the inflowing side of the storms.

Peak earthquake response of structures under multi-component excitations

Accurate estimation of the peak seismic responses of structures is important in earthquake resistant design. The internal force distributions and the seismic responses of structures are quite complex, since ground motions are multidirectional. One key issue is the uncertainty of the incident angle between the directions of ground motion and the reference axes of the structure. Different assumed seismic incidences can result in different peak values within the scope of design spectrum analysis for a given structure and earthquake ground motion record combination. Using time history analysis to determine the maximum structural responses excited by a given earthquake record requires repetitive calculations to determine the critical incident angle. This paper presents a transformation approach for relatively accurate and rapid determination of the maximum peak responses of a linear structure subjected to three-dimensional excitations within all possible seismic incident angles. The responses can be deformations, internal forces, strains and so on. An irregular building structure model is established using SAP2000 program. Several typical earthquake records and an artificial white noise are applied to the structure model to illustrate the variation of the maximum structural responses for different incident angles. Numerical results show that for many structural parameters, the variation can be greater than 100%. This method can be directly applied to time history analysis of structures using existing computer software to determine the peak responses without carrying out the analyses for all possible incident angles. It can also be used to verify and/or modify aseismic designs by using response spectrum analysis.

A New Theory on the Origin and Nature of the Fine Structure Constant

The nature and the origin of the fine structure are described. Based on the vortex model and hydrodynamics, a comprehensible interpretation of the fine structure constant is developed. The vacuum considered to have superfluid characteristics and elementary particles such as the electron and Hydrogen molecule are irrotational vortices of this superfluid. In such a vortex, the angular rotation ω is maintained, and the larger the radius, the slower the rotational speed. The fine structure value is derived from the ratio of the rotational speed of the boundaries of the vortex to the speed of the vortex eye in its center. Since the angular rotation is constant, the same value was derived from the ratio between the radius of the constant vortex core and the radius of the hall vortex. Therefore, the constancy of alpha is an expression of the constancy relation in the vortex structure.

Sensitivity analysis for axis rotation diagrid structural systems according to brace angle changes

General regular shaped diagrid structures can express diverse shapes because braces are installed along the exterior faces of the structures and the structures have no columns. However, since irregular shaped structures have diverse variables, studies to assess behaviors resulting from various variables are continuously required to supplement the imperfections related to such variables. In the present study, materials elastic modulus and yield strength were selected as variables for strength that would be applied to diagrid structural systems in the form of Twisters among the irregular shaped buildings classified by Vollers and that affect the structural design of these structural systems. The purpose of this study is to conduct sensitivity analysis for axial rotation diagrid structural systems according to changes in brace angles in order to identify the design variables that have relatively larger effects and the tendencies of the sensitivity of the structures according to changes in brace angles and axial rotation angles.

LAMELLAR MICROSTRUCTURE IN DUPLEX Ti-Al-V INTERMETALLIC COMPOUND

The morphology and crystallographic orientation of(α_2+γ)lamellar structure in duplex Ti-47.5Al-2.5V intermetallic compound have been studied by means of TEM, microdiffraction as well as 180° and non-180° rotation twinning analysis.A possible atomic model of the interface was suggested.Thus,approach was made to a mechanism on complex nucleation of α_2+γ two phases along α-Ti interface,and growth of α_2/γ/γ_1/α_2 or α_2/γ/α_2/γ as fundamental structural unit.

High-k Structures in (124)～Cs

High spin states in the odd-odd nucleus 124Cs have been investigated through the fusion-evaporation reaction 116Sn（11B, 3n）l24 Cs with a beam energy of 45 MeV. A new rotational band is established and assigned as the high-k configuration of πg9/2140419/2＋ ⊙vh 11/2[523]7/2-. Some structures linking to this band have also been observed. According to the results of the excitation energy systematics, the lowest level of this band is assigned as 9-, and the 8- isomer bandhead has not been observed. Another isomer with a half life of 6.3 s has also been observed with its new decay paths established, Its excitation energy is raised by 79 keV, but its Iπ is not changed.