Effect Of Mass Distribution Research Articles

Pumping Up the Base: Deployment of Strong Emotion and Simple Language in Presidential Nomination Acceptance Speeches

Background and Method: This research examines the nomination acceptance speeches of US presidential candidates from Republican and Democratic parties in the post-WWII mass communication era (1948–2020, 38 speeches). Variables studied are the emotional tone of the speeches, their abstractness, their Grade Level, their employment of personal pronouns and their mentions of “America”. Speeches were scored with the Dictionary of Affect in Language (a sentiment analysis tool).Predictions: On the basis of functionalist theories of political discourse, it was predicted that the speeches would have a pleasant and active or celebratory emotional tone. Based on related research that focused on the effects of mass distribution on presidential communications, it was predicted that the speeches would increase in pleasantness, arousal and linguistic simplicity across years.Results: As predicted, speeches were pleasant and active in tone. Across years, speeches became significantly more arousing, less abstract, simpler, and longer. When individual speeches were divided into five equal portions, a strong significant quadratic trend was observed for pleasantness, which started high at the beginning of a speech, fell in the center, and rose again at the end.Conclusions: Presidential nomination acceptance speeches are emotionally pleasant and active and linguistically simple (Grade 8 level). Between 1948 and 2020, they remained pleasant, and became more active and simpler. In service of their aim to “pump up the base” individual speeches began on a pleasant, nationalistic and personal note, encompassed duller and more impersonal material in their centers, and became positive again at the end.

High-fidelity landing simulation of small body landers: Modeling and mass distribution effects on bouncing motion

The surface dynamics of small bodies is a key problem for landing and sample return missions. It is also very meaningful for the research of morphologic evolution of small bodies. However, such surface dynamics problem is so difficult that the high-fidelity simulation of a lander on and above the surface of a small body is still a big challenge. This paper proposes a method to simulate six degrees of freedom motion of arbitrary-shaped landers in the neighborhood of a small body with multi-contact. In detail, the contacts between the lander and the small body are processed by utilizing the Polygonal Contact Model (PCM). Considering the orbital and attitude dynamics, the dynamical model of a lander in six degrees of freedom is constructed over a small body. Some specific issues in the numerical integration are addressed and figured out. Furthermore, two methods are proposed to reduce the computational cost significantly, which make the Monte Carlo simulations feasible. Finally, the effect of the lander mass distribution on its bouncing motion is investigated parametrically to illustrate the effectiveness of the above method.

Effect of mass distribution on curving performance for a loaded wagon

The location of wagon gravity center for a loaded wagon is underestimated in a vehicle–track coupled system. The asymmetric wheel load distribution due to loading offset significantly affects the wheel-rail contact state and seriously deteriorates the curving performance in conjunction with the height of gravity center and cant deficiency. Optimizing the location of gravity center and cruising velocity, therefore, is of interest to prevent the derailment and promote the transport capacity of railway wagons. This study aims to reveal the three-dimensional influencing mechanism of mass distribution on vehicle curving performance under different velocities. The wheel unloading ratio is regarded as the evaluation index. A simplified quasi-static model is established considering essential assumptions to highlight the influence of lateral and vertical offset on curving performance. For a more accurate description, the MBS models with various locations of wagon gravity center are built and then negotiate curves in different simulation cases. The simulation results reveal that the distribution of wheel unloading ratio determined by loading offset is like contour lines of ‘basin’. Based on the conclusions of quasi-static analysis and dynamics simulations, the regression equation is proposed and the fitting parameters are calculated for each simulation case. This paper demonstrates the necessity of optimizing the location of wagon gravity center according to the running condition and offers a novel strategy to load and transport the cargo by railway wagons.

Effect of mass distribution and collection angle in pulsed laser deposited films – a sampling method for chemical characterization of spent nuclear fuel

Effect of mass distribution and collection angle in PLD films from a single target having a wide mass range (24 to 238 amu).

Aeroelastic Instability of Flexible Rocket Bodies on the Basis of a Simplified Mechanical Model

The present paper deals with the applicability of simplified mechanical models to discuss the aeroelastic instability behavior of flexible rocket bodies. A suitable mechanical model to demonstrate body divergence and flutter has been discussed and the stability analysis of the model has been presented. The flutter criterion requires a computation of the characteristic polynomial. Sylvester’s dialytic method of elimination is used to compute the required discriminant. A mechanical model composed of three bars, connected together by two elastic rotational springs, having five degrees-of-freedom is chosen for demonstrating both divergence and flutter instabilities. Effects of mass distribution, stiffness distribution, and location of stabilizer fin on instability behavior are discussed.

Studying the Disturbances of Robotic Arm Movement in Space Using the Compound-Pendulum Method

Целью статьи является исследование помех, которые возникают при использовании роботизированного манипулятора с нагрузкой и влияют на общую динамическую модель летательного аппарата, привнося моменты и силы, представляющие собой дополнительный шум. Летательный аппарат, используемый в данном исследовании, представляет собой многороторный БПЛА (беспилотный летательный аппарат). Помехи, оказывающие влияние на центр тяжести летательного аппарата, изменяются по времени вследствие изменения углов движения роботизированного манипулятора во всех направлениях, что определяет зависимость уравнения движения от времени. Данная статья предлагает комплексное исследование по определению моментов инерции летательного аппарата с использованием упрощенного метода маятника, учитывающее влияние распределения массы и изменения центра тяжести, которые являются результатом непрерывного движения манипулятора при движении летательного аппарата в воздухе. Для получения по возможности наиболее полного представления помех экспериментальные испытания проводились с использованием программного обеспечения SolidWorks и оценивались с использованием MATLAB. Конечным результатом исследования является создание точного уравнения движения и разработка контроллеров для обеспечения его устойчивости и стабильности.

Gravitational and mass distribution effects on stationary superwinds

Here, we model the effect of non-uniform dynamical mass distributions and their associated gravitational fields on the stationary galactic superwind solution. We do this by considering an analogue injection of mass and energy from stellar winds and SNe. We consider both compact dark-matter and baryonic haloes that does not extend further from the galaxies optical radii $R_{\rm opt}$ as well as extended gravitationally-interacting ones. We consider halo profiles that emulate the results of recent cosmological simulations and coincide also with observational estimations from galaxy surveys. This allows to compare the analytical superwind solution with outflows from different kinds of galaxies. We give analytical formulae that establish when an outflow is possible and also characterize distinct flow regimes and enrichment scenarios. We also constraint the parameter space by giving approximate limits above which gravitation, self-gravitation and radiative cooling can inhibit the stationary flow. We obtain analytical expressions for the free superwind hydrodynamical profiles. We find that the existence or inhibition of the superwind solution highly depends on the steepness and concentration of the dynamical mass and the mass and energy injection rates. We compare our results with observational data and a recent numerical work. We put our results in the context of the mass-metallicity relationship to discuss observational evidence related to the selective loss of metals from the least massive galaxies and also discuss the case of massive galaxies.

The efficiency of dynamic relaxation methods in static analysis of cable structures

Nine different schemes of dynamic relaxation method are compared in the paper. Schemes with viscous damping and schemes with kinetic damping are used. Kinetic damping with a peak in the middle of the time step and kinetic damping with the parabolic approximation of the peak are considered. They are also used in three different ways of cable approximation. The cable is approximated as a tension bar, a catenary and a parabolic cable element. The efficiency and stability of each method are compared to three selected 3D examples of cable structures and one existing structure. The effect of mass distribution along the structure is also of interest and is studied in the paper.

Efficiency of Dynamic Relaxation Method in Form-Finding Process of Cable-Membrane Structures

This study is focused on the form-finding process of cable-membrane structures using the dynamic relaxation method with kinetic damping. Eight different schemas of the dynamic relaxation method are compared in the paper. The effect of mass distribution along the structure is also of interest. The efficiency and stability of each process are compared on selected 3D examples of cable-membrane structures.

The Efficiency of Dynamic Relaxation Methods in Static Analysis of Cable-Membrane Structures

This paper is focused on the static analysis of cable-membrane structures using the dynamic relaxation method. Several different processes of dynamic relaxation method are compared in this paper. The techniques with viscous damping and the techniques with kinetic damping are used. The efficiency and stability of each process are compared to selected 3D examples of cable-membrane structures. The effect of mass distribution along the structure is also of interest and it is studied in the paper.

Estimation of Tension Force in Short Hangers Using Added Mass Method

For short hangers, the influence of flexural rigidities and boundary conditions on tension measuring cannot be neglected. But there has no effective method to precisely calculate hanger tension considering the two parameters. This paper proposes the Added Mass Method (AMM) to simultaneously identify the tension, flexural rigidity and boundary condition of short hangers. In this method, the effect of mass distribution of structure on natural frequencies has been studied to add extra calculation conditions for establishing the eigenvalue equation set. The method of Genetic Algorithm (GA) with adaptive crossover and mutation rate is used to solve the equation set quickly. The results provides that the AMM is a high-accurate field testing technology in tension measurement for short hanger of arch bridge.

A distributed-mass approach for dynamic analysis of Timoshenko plane frames

The dynamic stiffness method is the exact method for the dynamic analysis of plane frames using the continuous-coordinate system to consider the effect of mass distribution in beam elements. The dynamic stiffness method may create some null modes where the joints of beam element have null deformation. Unlike the Bernoulli–Euler frames, adding an interior node at the middle of the beam elements cannot normalize all the null modes of flexural vibration in the Timoshenko frames. The floating interior-node scheme is proposed to eliminate the null modes of flexural vibration in the Timoshenko frames. Orthogonal properties of vibration modes in Timoshenko plane frames are theoretically derived, through which the equations of motion in beam elements can be transformed into the decoupled equations of motion in terms of mode amplitudes.

Geometry of Potential Models

With the help of the description of geometry of potential methods and the gravity models, we tried to briefly explain these models’ application and applicability. Our aim was to show what may be concluded from different potential models. To answer this question, traffic data were compared to the values predicted by the models. We found that the values of the regression showed a moderately strong correlation. We could determine that the conclusions drawn from the potential models should be treated with reservations. According to the analysis of the potential models it is not possible to determine in case of a potential value whether it results from positive/negative (municipal, spatial) structure or position, or the location of masses, area size or the impact of its own mass. Thus, the mathematical method described in this study tried to separate the potentials. We found that accessibility potential was dependent on spatial subdivision to the highest degree, but important factors were the effect of mass distribution as well as of own mass

Perceiving action-relevant properties of tools through dynamic touch: Effects of mass distribution, exploration style, and intention.

At issue in the present series of experiments was the ability to prospectively perceive the action-relevant properties of hand-held tools by means of dynamic touch. In Experiment 1, participants judged object move-ability. In Experiment 2, participants judged how difficult an object would be to hold if held horizontally, and in Experiments 3 and 4, participants rated how fast objects could be rotated. In each experiment, the first and second moments of mass distribution of the objects were systematically varied. Manipulations of wielding speed and orientation during restricted exploration revealed perception to be constrained by (a) the moments of mass distribution of the hand-tool system, (b) the qualities of exploratory wielding movements, and (c) the intention to perceive each specific property. The results are considered in the context of the ecological theory of dynamic touch. Implications for accounts of the informational basis of dynamic touch and for the development of a theory of haptically perceiving the affordance properties of tools are discussed.

A distributed-mass approach for dynamic analysis of Bernoulli–Euler plane frames

The exact dynamic analysis of plane frames should consider the effect of mass distribution in beam elements, which can be achieved by using the dynamic stiffness method. Solving for the natural frequencies and mode shapes from the dynamic stiffness matrix is a nonlinear eigenproblem. The Wittrick–Williams algorithm is a reliable tool to identify the natural frequencies. A deflated matrix method to determine the mode shapes is presented. The dynamic stiffness matrix may create some null modes in which the joints of beam elements have null deformation. Adding an interior node at the middle of beam elements can eliminate the null modes of flexural vibration, but does not eliminate the null modes of axial vibration. A force equilibrium approach to solve for the null modes of axial vibration is presented. Orthogonal conditions of vibration modes in the Bernoulli–Euler plane frames, which are required in solving the transient response, are theoretically derived. The decoupling process for the vibration modes of the same natural frequency is also presented.

Lightening structure optimization on turbine wheel of vehicular turbocharger

Based on basic principle of optimization design, structure optimization of turbine is conducted using optimization module of ANSYS and APDL in order to get the minimum turbine weight. Meanwhile, the original blade profile and flow passage are maintained, and the structural strength of the turbine are guaranteed. Considering assembly technique and cast requirement, the structure of the modified turbine is determined which can save 6.91 percent of the material compared with the original one. The modified turbine not only saved material, but also gained better effect of mass distribution between the turbine and the compressor impeller. The result can provide useful reference to engineering application of turbocharger.

Modelling and simulation of a feed drive using the transmission line modelling technique

The paper focuses on the modelling and simulation of a test rig and a digital drive is based on the transmission line modelling technique. The rig is a positioning system equivalent to a CNC machine tool feed drive. Accurate representations of dynamic systems included in electromagnetic, power electronic and some mechanical applications have been obtained until now by applying the transmission line modelling technique. The paper proposes a novel application of th~s method for simulation of closed loop control of the position of a test rig. The model includes the distributed parameter dynamics of the feed drive and the effect of mass distribution. This is based on the flexibility of transmission line modelling to develop lumped and distributed parameter systems. Also a transmission line model for the controller integrated into the digital drive is developed. Encouraging simulation results are obtained by using MATLAB. In this way, the CNC machine tools feed drives could be modelled with increasing accuracy as hybrid, distributed-lumped representations using numerical methods.

The dynamic response of a three-leg articulated tower

Articulated towers are a compliant type of platform particularly suited for deep water applications. In the design of articulated towers, it is very important that the motion characteristics include sufficient stability, less acceleration in the deck and the smallest possible loading on the articulated joint. The mass distribution along the tower also plays an important role in the motion characteristics of the tower. Multi-leg articulated towers with three or more towers (legs or shafts), which have been developed from the conventional single tower have reduced horizontal movements and have more deck area compared to the single-leg articulated towers. The experimental and analytical investigations on such towers are not available in the published literature. In this paper, both analytical treatment and an experimental program for a three-leg articulated tower model have been reported. The effect of mass distributions on the variations of the bending moment and the deck accelerations are also presented. The model has been tested in a 2 m wave flume for various wave frequencies and wave heights of regular waves. The model is also analysed using a computer program developed, and the comparison of theoretical results with the experimental results is presented.

Effect of Radiation on the Nonlinear Stability Zones of the Lagrangian Equilibrium Points

The nonlinear stability zones of the triangular Lagrangian points are determined numerically and the effect of radiation of primaries is considered, in addition to the known effect of mass distribution, using the photogravitational restricted three‐body problem model. It is found that radiation also has a considerable effect reducing the stability zones. In cases of resonances, these zones are reduced to negligible size for some parameter values within the linear stability regions.

Effects of CG Location on the Launch Behavior of Free-Fall Lifeboats

Abstract The free-fall lifeboat was developed to reduce the risk of injury during evacuation in a maritime emergency. It is a generally accepted concept for lifesaving appliances that currently is in use on many ships and offshore platforms. Three concerns during launch of these lifeboats are the attitude of the boat at water entry, the headway immediately after water entry, and the acceleration forces to which the occupants are subjected. Limited quantitative data is available about the behavior of the boats during launch and, in particular, on the effects of mass distribution on the launch behavior of free-fall lifeboats. The purpose of this paper is to discuss quantitatively the launch behavior of free-fall lifeboats, with particular emphasis on the effects of changes in the location of the CG.