Bracket Structure Research Articles

수치분석을 통한 부석사 무량수전의 평면과 단면 특성에 관한 연구

Korean wooden architecture has been changed continuously. Murayangsu-jeon in Buseok Temple has special meaning and historial significance in the history of Korean wooden architecture. Because it is one of the oldest and few wooden buildings built in Korea Dynasty. In order to determine the characteristics of floor plan and section in the view point of architectural design, this study analyze the measurement of materials which consist of bracket system and structure. The result of this study is as follows; The basic scale applied to this building is that 1 ja is probably 303mm. With this scale, the bay of the facade was designed as 10+14+14+14+10 ja and the one of the side was designed as 10+18+10 ja. The height of the section was designed as repetition of materials which have the same size and that is one of the major characteristics showed from architecture of Korea Dynasty. In addition, it is determined that Muryangsu-jeon was repaired in <TEX>$14^{th}$</TEX> Century as we can see in the records but has the style of <TEX>$11^{th}$</TEX> Century when it was built first.

The Optimization Calculation and Analysis of Trough Solar Collector Bracket System

The parabolic trough-type collectors and new bracket system were accounted for the research object; static load and structural optimization were analyzed by ANSYS, and selected the best section size of the bracket with meet the strength and stiffness requirements. The results show that the original bracket structure almost meet the strength and stiffness requirements under normal working conditions; After optimization design, the weight of bracket system decreased by 10.68%, so greatly save the production cost under meeting the conditions of strength and stiffness requirements.

A Deformation Analysis and Compensation Algorithm for Bracket Structure of Automatic Drill-Riveting System

Since the bracket deformation caused by its deadweight is too large, and the riveting of aircraft panel is always over-tolerance, a new algorithm for analysis and compensation of bracket deformation is presented in this paper. The algorithm is formed by combining finite element (FE) simulation with analytic method, which is fit for different combinations of supporting plates of bracket system. The formula is constructed through cubic spline interpolation and envelope surface fitting according to the FE simulation data. Meanwhile, a corresponding compensation method is proposed. Finally, a numerical simulation example with the software of ABAQUS shows that the algorithm and its results are valid and feasible.

Discrete Integrable Systems and Poisson Algebras From Cluster Maps

We consider nonlinear recurrences generated from cluster mutations applied to quivers that have the property of being cluster mutation-periodic with period 1. Such quivers were completely classified by Fordy and Marsh, who characterised them in terms of the skew-symmetric matrix that defines the quiver. The associated nonlinear recurrences are equivalent to birational maps, and we explain how these maps can be endowed with an invariant Poisson bracket and/or presymplectic structure. Upon applying the algebraic entropy test, we are led to a series of conjectures which imply that the entropy of the cluster maps can be determined from their tropical analogues, which leads to a sharp classification result. Only four special families of these maps should have zero entropy. These families are examined in detail, with many explicit examples given, and we show how they lead to discrete dynamics that is integrable in the Liouville-Arnold sense.

POSITION OPERATORS AND CENTER-OF-MASS: NEW PERSPECTIVES

After reviewing the work of Pryce on Center-of-Mass (CoM) definitions in special relativity, and that of Jordan and Mukunda on position operators for relativistic particles with spin, we propose two new criteria for a CoM candidate: associativity, and compatibility with the Poisson bracket structure. We find that they are not satisfied by all of Pryce's definitions, and they also rule out Dixon's CoM generalization to the curved space–time case. We also emphasize that the various components of the CoM position do not commute among themselves, in the general case, and thus provide a natural entry point to the arena of noncommutative space–time, without the ad-hoc assumptions of the standard paradigm.

Evaluation of Friction of Different Ligation Methods In Accordance With and Without Bracket Types

ABSTRACT Objective: The aim of this in vitro study was to evaluate the frictional values of 3 different ligation methods with different bracket types using a crowded configuration. Materials and Methods: Three aesthetic conventional brackets (monocrystalline ceramic, polycrystalline ceramic, microfilled copolymer) and 1 metal bracket were evaluated in terms of friction. All brackets were tested in a crowded configuration of bracket alignment with 0.014 nickel titanium archwire in place. All brackets were ligated with metal ligatures, elastomeric ligatures, and nonconventional elastomeric ligatures. For accurate and repeatable placement on metal plates, a special jig was designed. The pulling speed was set to 10 mm/min for 30 seconds for each sample. Results: When bracket structure was not considered, nonconventional elastomeric ligature produced the lowest friction. For brackets ligated with elastomeric modules, microfilled copolymer bracket showed the lowest friction and monocrystalline ceramic bracket s...

The Optimization Design of Arm Bracket Structure Topology Based on ANSYS

The detail analysis proposal of the cylinder body is put forward for the automatic tool change mechanism of the QYJ-21 type horizontal machining center. It consists of three main aspects. Firstly, the dimensional model of the cylinders arm bracket portion will be created. Secondly, the topology optimization design of the arm bracket is implemented based on ANSYS Workbench. Finally, meeting the stiffness requirements, the optimal topology shape will be established, for it had the lightest weight.

Assessing near infrared optical properties of ceramic orthodontic brackets using cross‐polarization optical coherence tomography

Secondary decay (caries) under ceramic orthodontic brackets remains a significant dental problem and near infrared cross-polarization optical coherence tomography (CP-OCT) has the potential to detect underlying demineralization. The purpose of this study was to determine the effect of crystalline structure and chemical composition of ceramic brackets on CP-OCT imaging. Four ceramic brackets types, which were divided into monocrystalline and polycrystalline, were examined using CP-OCT. The results of this study demonstrated that the crystallinity of the ceramic brackets affected the 1310 nm CP-OCT imaging with the greatest attenuation seen in polycrystalline alumina brackets. The alumina polycrystalline bracket materials had significantly higher attenuation and scattering than alumina monocrystalline brackets (p < 0.05, ANOVA, Bonferroni). Additionally, bracket base morphology and composition affected NIR light attenuation. There was considerable attenuation in bracket bases that contained additive zirconium spheres (∼30 µm) and this alteration was significantly greater than the jagged alumina crystallographic alterations found in the other bracket systems (p < 0.05, ANOVA, Bonferroni). Noninvasive, near infrared (NIR) cross-polarization optical coherence tomography (CP-OCT) has potential to effectively image through portions of ceramic brackets; however, further investigation into the optical effects of resin integration in the base portion of the brackets is warranted.

Numerical Analysis of Deformation and Failure of Penetration into Concrete Target by Projectile

Penetration is an important topic in the military and protection engineering field. Based on *MAT_PLASTIC_KINEMATIC of LS-DYNA program, this report studies effects of failure strain of the material parameters on structure of penetrating projectile. By establishing a group of numerical models about 45 steel hemispherical projectile penetrating semi-infinite concrete targets, this research aimed at analyzing effects of different failure strain values related to the destruction of the internal bracket structures of this projectile. At the same time, it studied the criterion of failure on finite dynamic program. The numerical results show that the use of failure strain in this model can well simulate damage of internal bracket structures of the projectile. Test was carried on based on this conclusion, which showed that bracket plate is subjected to shear failure in process of penetration, and numerical simulation was consistent with the experimental results.

FEM Based Statics Analysis of the Main Steel Structure of Bucket Wheel Stacker-Reclaimer

Bucket wheel stacker-reclaimer is kind of a typical multi-rigid-body system. Its main steel structure consists of bucket wheel, forearm frame, column tower, balance frame and pull rod, etc. All components connected with each other basically by welding. And the integral structure can realize whole luffing motion and turning motion. Reclaiming arm, central bracket and pitch steel structure of counterweight arm are the structure of its core. This paper use ANSYS to create the simplified finite element model of the steel structure and analyze the distribution of loads in all types of conditions. Loading solving, then cloud picture of displacement and that of stress of the overall luffing mechanism was concluded, so as to check the carrying capacity and strength of the structure.

Welding of large support bracket components (Type V) of ship propeller shafts

We present the practical aspects of qualification of a welding procedure for the large-size structure of brackets of screw shafts made of cast steel and performance of a real welding operation. The issue of qualification of welding procedures, conducting assembly-welding works coupled with their monitoring and local heat treatment of welded joints as well as some aspects of non-destructive testing of welds are discussed. The whole work was supervised by Lloyd's Register of Shipping.

Lifting particle coordinate changes of magnetic moment type to Vlasov-Maxwell Hamiltonian dynamics

Techniques for coordinate changes that depend on both dependent and independent variables are developed and applied to the Maxwell-Vlasov Hamiltonian theory. Particle coordinate changes with a new velocity variable dependent on the magnetic field, with spatial coordinates unchanged, are lifted to the field theoretic level, by transforming the noncanonical Poisson bracket and Hamiltonian structure of the Vlasov-Maxwell dynamics. Several examples are given including magnetic coordinates, where the velocity is decomposed into components parallel and perpendicular to the local magnetic field, and the case of spherical velocity coordinates. An example of the lifting procedure is performed to obtain a simplified version of gyrokinetics, where the magnetic moment is used as a coordinate and the dynamics is reduced by elimination of the electric field energy in the Hamiltonian.

쌍봉사 대웅전의 조영에 관한 고찰 - 탑신부(塔身部)의 구조와 의장을 중심으로 -

In Korea, only a few wooden pagodas are extant because some wooden pagodas were lost due to artificial environment like war. Fortunately, only Eight Depictions Hall(Palsangjeon) in Beobjusa temple and main hall of Ssang-Bong Sa the main temple are extant. Though main hall of Ssang-Bong Sa the main temple shows old style in construction and outstanding creativity, survey and investigation for the hall have been poor. Accordingly, this study investigated pillar part, bracket structure part, and roof part composing pagoda body section which actively reflects structure and design skill compared to floor or upper part. And for better understanding, in the part that is similar to pagoda body section of main hall or needs examples, wooden pagoda in China or Japan was referred. Through this investigation, it was known that unique skill applied to main hall of Ssang-Bong Sa the main temple is based on plane in one room <TEX>${\times}$</TEX> one room - Ssang-Bong Sa the main temple has common form of wooden pagoda in appearance.

Vlasov moment flows and geodesics on the Jacobi group

By using the moment algebra of the Vlasov kinetic equation, we characterize the integrable Bloch-Iserles system on symmetric matrices [Bloch, A. M., Brînzănescu, V., Iserles, A., Marsden, J. E., and Ratiu, T. S., “A class of integrable flows on the space of symmetric matrices,” Commun. Math. Phys. 290, 399–435 (2009)]10.1007/s00220-009-0849-6 as a geodesic flow on the Jacobi group \documentclass[12pt]{minimal}\begin{document}${\rm Jac}(\mathbb {R}^{2n})={\rm Sp}(\mathbb {R}^{2n})\,\circledS \,{\rm H}(\mathbb {R}^{2n})$\end{document} Jac (R2n)= Sp (R2n)ⓈH(R2n). We analyze the corresponding Lie-Poisson structure by presenting a momentum map, which both untangles the bracket structure and produces particle-type solutions that are inherited from the Vlasov-like interpretation. Moreover, we show how the Vlasov moments associated to Bloch-Iserles dynamics correspond to particular subgroup inclusions into a group central extension (first discovered by Ismagilov, Losik, and Michor [“A 2-cocycle on a group of symplectomorphisms,” Mosc. Math. J. 6, 307–315 (2006)]), which in turn underlies Vlasov kinetic theory. In the most general case of Bloch-Iserles dynamics, a generalization of the Jacobi group also emerges naturally.

Checking Computation for Bracket Structure of Jinqinggang Bridge

In order to ensure the safety of bracket structure during the cast-in-place construction of No.0 and No.1 piece concretes, this paper makes use of probabilistic limit state method to do the checking computation. According to the design drawings of bracket structure of the Jinqinggang bridge and the actual load case, the analytical model is founded by the finite element analysis software MIDAS/CIVIL. The results show that the stresses of all parts of the bracket structure including the concrete local compressive stress and the tensile stress of embedded steel bar are less than the allowed value of corresponding materials, but the deformation of the steel moulding plate is larger than standard allowance value. The weld joint between upper chord and slanting pole with embedded steel plate satisfies the design requirement.

Design of Movable Bracket for Dual-Axis Tracking Solar Thermal Power System

Movable bracket as an important part of dual-axis tracking solar thermal power system is large, movable and complex of its force with the orbit of connected nodes. At the same time, the system has strict requirements on removable bracket’s deformation. The technical feasibility and the cost lever of the bracket structure play decisive roles in the promotion of the application of this new type of solar thermal power system. This paper clarifies the applications operation of solar power system on the basis of the principle of the performance of the support structure for the system requirements, summarizes the mechanical characteristics of the bracket structure, combined with the analysis of the pilot project support structure selection, expounds the key points of structural selection, and determines a more reasonable form of the support structure.

Rational Calogero-Moser Model: Explicit Form and r-Matrix of the Second Poisson Structure

We compute the full expression of the second Poisson bracket structure for N=2 and N=3 site rational classical Calogero-Moser model. We propose an r-matrix formulation for N=2. It is identified with the classical limit of the second dynamical boundary algebra previously built by the authors.

A global hexagonal C‐grid non‐hydrostatic dynamical core (ICON‐IAP) designed for energetic consistency

AbstractThis study describes a new global non‐hydrostatic dynamical core (ICON‐IAP: Icosahedral Nonhydrostatic model at the Institute for Atmospheric Physics) on a hexagonal C‐grid which is designed to conserve mass and energy. Energy conservation is achieved by discretizing the antisymmetric Poisson bracket which mimics correct energy conversions between the different kinds of energy (kinetic, potential, internal). Because of the bracket structure this is even possible in a complicated numerical environment with (i) the occurrence of terrain‐following coordinates with all the metric terms in it, (ii) the horizontal C‐grid staggering on the Voronoi mesh and the complications induced by the need for an acceptable stationary geostrophic mode, and (iii) the necessity for avoiding Hollingsworth instability. The model is equipped with a Smagorinsky‐type nonlinear horizontal diffusion. The associated dissipative heating is accounted for by the application of the discrete product rule for derivatives. The time integration scheme is explicit in the horizontal and implicit in the vertical. In order to ensure energy conservation, the Exner pressure has to be off‐centred in the vertical velocity equation and extrapolated in the horizontal velocity equation.Test simulations are performed for small‐scale and global‐scale flows. A test simulation of linear non‐hydrostatic flow over a rough mountain range shows the theoretically expected gravity wave propagation. The baroclinic wave test is extended to 40 days in order to check the Lorenz energy cycle. The model exhibits excellent energy conservation properties even in this strongly nonlinear and dissipative case. The Held–Suarez test confirms the reliability of the model over even longer time‐scales. Copyright © 2012 Royal Meteorological Society

The influence of adhesives and the base structure of metal brackets on shear bond strength

The objective of this study was to investigate the shear bond strength of compound made of tooth enamel, adhesive, and brackets for certain material combinations according to the DIN 13990-2 standard. We examined a combination of the following materials on permanent bovine incisors: (1) adhesives: Light Bond™ and Phase II® (both produced by Reliance Orthodontic Products, Itasca, IL, USA), TransbondXT™ (3M Unitek, Monrovia, CA, USA), (2) brackets: Carriere®, Euro Midi Classic, Midi Low Friction (all from Ortho Organizers, Carlsbad, CA, USA). The discovery® bracket (Dentaurum, Ispringen, Germany) served as the reference. According to the DIN standard, the teeth were embedded, adhesive was applied and they were then put into storage. This was followed by shear tests in a material testing machine with the shear force acting directly on the bracket base in the occlusal-gingival direction. Finally, the Adhesive Remnant Index was determined. We observed the greatest shear bond strength (mean value) from the combination of Carriere® and TransbondXT™ (17.4N/mm(2)), and the lowest from the combination of Euro Midi Classic and Phase II® (12.8N/mm(2)). There were significant differences in the various material combinations. The values obtained from the measurements of discovery® together with TransbondXT™ agreed very well with the results of previous investigations. The combinations of brackets and adhesives investigated in this study according to DIN standard 13990-2 provided a satisfactory result for clinical use.

Roth versus traditional accounts in a life-cycle model with tax risk

AbstractThis paper analytically solves a life-cycle model that compares traditional and Roth retirement accounts. It includes realistic features such as tax deductibility of contributions and taxation of withdrawals, tax bracket structure with deductions, taxation of Social Security benefits, and tax risk at retirement. With current taxes, choosing a traditional account over a Roth creates small welfare losses in only a few cases, largely for those with higher incomes and pensions who are subject to the taxation of Social Security benefits. We also investigate tax variability and find that diversified strategies offer only small risk reduction benefits in our illustrations.