bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlling ion channel function with renewable recombinant antibodies
Authors: Colecraft Henry M. , Trimmer James S. 
Published: March 2022

AbstractSelective ion channel modulators play a critical role in physiology in defining the contribution of specific ion channels to physiological function and as proof of concept for novel therapeutic strategies. Antibodies are valuable research tools that have broad uses including defining the expression and localization of ion channels in native tissue, and capturing ion channel proteins for subsequent analyses. In this review, we detail how renewable and recombinant antibodies can be used to control ion channel function. We describe the different forms of renewable and recombinant antibodies that have been used and the mechanisms by which they modulate ion channel function. We highlight the use of recombinant antibodies that are expressed intracellularly (intrabodies) as genetically encoded tools to control ion channel function. We also offer perspectives of avenues of future research that may be opened by the application of emerging technologies for engineering recombinant antibodies for enhanced utility in ion channel research. Overall, this review provides insights that may help stimulate and guide interested researchers to develop and incorporate renewable and recombinant antibodies as valuable tools to control ion channel function.
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UPed: A Quadruped Robot Platform to Study Directional Leg Compliance
Authors: Gurney Jason , Samare Filsoofi Ali , McClain Eric , Bolejack Chris , Aboufazeli Mahtab , John Mathews V. , Meek Sanford 
Published: March 2022

Abstract
This paper presents UPed, a quadruped robot platform, for studying passive, directional, leg compliance in robots. This work was motivated by the benefits provided by passively and directionally compliant legs in humans and animals. UPed uses under-actuated legs based on the bent-knee model which is capable of changing the direction and magnitude of the leg compliance by adjusting the knee angle and distal leg stiffness. Pneumatic pistons were chosen as variable compliance elements, enabling the leg compliance to be adjusted during locomotion. The platform was validated experimentally by evaluating how the robot’s pitch rate and cost of transport changed with variations in leg compliance and knee angle. Results of these experiments indicated that significant performance improvements are possible by selecting appropriate values of compliance and knee angle. They also demonstrated a unique capability to explore adjustable directional compliance and other parameters in robot legs on a physical robotic system. UPed has the potential to facilitate significant performance improvements of legged robots by enabling additional in-depth studies on directional passive leg compliance.
Design and Analysis of Both Dimensional and Geometric Tolerances in a Variational Geometry-Based Design Environment
Authors: Dong Jian 
Published: March 2022

Abstract
This paper describes an ongoing research on developing an analytical approach to optimal allocation of both dimensional and geometric tolerances. Current researches and industrial practices only focus on dimensional tolerances allocations, and geometric tolerances are not considered. Four major issues are discussed in this paper, they are: (1) analyzing constraint variations and tolerance sensitivity in a variational geometry-based design environment, (2) establishing an optimization model for allocating both geometric and dimensional tolerances, (3) identifying the geometric and manufacturing relationships between dimensional and geometric tolerances, (4) solving the optimization model and comparing the results. As an example, the optimal allocation of both dimensional and geometric tolerances for a precision slideway is presented.
Product Modularization for Reuse and Recycling
Authors: Sosale Swaroop , Hashemian Mehdi , Gu Peihua 
Published: March 2022

Abstract
Modular products consist of detachable modules, some of which may be recyclable, reusable or remanufacturable upon product retirement. This paper presents an integrated modular design methodology for environment conscious design and manufacturing. The methodology identifies the factors related to the design objectives, relates these factors to design components through interaction analysis, and clusters components into modules. An example is provided to illustrate the methodology and the algorithms.
Evaluating Reuse and Remanufacture Potential Using a Simple Model for Product Value
Authors: Sutherland John W. , Daniel Cecil M. , Vadrevu Srikanth , Olson Walter W. 
Published: March 2022

Abstract
Manufacturers around the world are currently evaluating new strategies to effectively utilize resources and enhance their competitiveness in the marketplace. Global concern about the environmental impacts of the manufacture and use of a multitude of products have led manufacturers to consider extensive reuse, remanufacture and recycling of products. Today, manufacturers also face legislation to “take back” their used products. Over the useful life of a product, changes occur in the mean and variance of the performance parameters. A new metric “satisfaction” has been introduced that combines the benefits and losses associated with use of the product. The change in product performance over its useful life is modeled by extending the concepts of loss and benefit over a third dimension — time. An estimate of product value may now be made at any point in the useful life of a product. A knowledge of the value could guide such decisions as the optimum time at which to remanufacture a product. Additionally, the model of product value may facilitate creation of an environmentally friendly product by raising issues such as performance degradation and reusability early in the design stage.
Analysis of Fluid-Structure Interaction by Means of Dynamic Unstructured Meshes
Authors: Blom F. J. , Leyland P. 
Published: March 2022

Abstract
This paper presents a computational analysis on forced vibration and fluid-structure interaction in compressible flow regimes. A so-called staggered approach is pursued where the fluid and structure are integrated in time by distinct solvers. Their interaction is then taken into account by a coupling algorithm. The unsteady fluid motion is simulated by means of an explicit time-accurate solver. For the fluid-structure interaction problems which are considered here the effects due to the viscosity can be neglected. The fluid is hence modeled by the Euler equations for compressible inviscid flow. Unstructured grids are used to discretise the fluid domain. These grids are particularly suited to simulate unsteady flows over complex geometries by their capacity of being dynamically refined and derefined. Dynamic mesh adaptation is used to enhance the computational precision with minimal CPU and memory constraints. Fluid-structure interaction involves moving boundaries. Therefore the Arbitrary Lagrange Euler method (ALE-method) is adopted to solve the Euler equations on a moving domain. The deformation of the mesh is controlled by means of a spring analogy in conjunction with a boundary correction to circumvent the principle of Saint Venant. To take advantage of the differences between fluid and structure time scales, the fluid calculation is subcycled within the structural time step. Numerical results are presented for large rotation, pitching oscillation and aeroelastic motion of the NACA0012 airfoil. The boundary deformation is validated by comparing the numerical solution for a flat plate under supersonic flow with the analytical solution.
A Finite Volume Method for the Computation of Fluid Flow With Moving Grid for Fluid-Structure Interactions
Authors: Mounsif S. , Mesquita A. L. Amarante 
Published: March 2022

Abstract
A finite-volume numerical method is presented for the solution of the two-dimensional incompressible, unsteady Navier-Stokes equations in general moving curvilinear co-ordinates. The method employs the semi-strong conservation form of the governing equations with pressure and physical contravariant velocity components as dependent variables. The k-ε model is utilised to describe the turbulent flow process. The SIMPLE algorithm is used to handle the pressure-velocity coupling. Results for the calculation of the fluctuating flow past an airfoil are compared with the available experimental data. As a simulation of fluid-structure interaction, the calculation of the unsteady flow-field around a stay-vane hydrofoil in forced and free vibration is presented. The numerical results obtained in this work show very good agreement with experimental observations.
Lift Coefficient Variation on a Cylinder Forced to Oscillate
Authors: Bernhardt John E. , Mihailovic Jadran , Jines Carlos F. , Abouel-Fotouh Aziz , Corke Thomas C. , Williams David R. 
Published: March 2022

Abstract
The instantaneous pressure distribution around the azimuth of a cylinder undergoing forced oscillations is measured using an array of 18 miniature microphones. The microphones were placed at the midspan of the cylinder with 20 degree increments between each sensor. The Reynolds number for the experiments was 13,800. The cylinder is driven in a sinusoidal motion by a printed circuit motor with an amplitude A/D = 0.18 and with bare winding numbers (Ω = f/fn) of 0 ≤ Ω ≤ 1.1. Regions of lock-in between the cylinder motion and the lift coefficient were observed at dressed winding numbers of ω = 2:3, 1:2 and 1:1. Phase diagrams show two distinctly different synchronization mechanisms, one fundamental and the other a subharmonic type, which supports the findings of Ongoren and Rockwell (1988).
A Physical Explanation of the Destabilizing Effect of Damping
Authors: Païdoussis M. P. , Semler C. , Alighanbari H. 
Published: March 2022

Abstract
In this paper, the destabilization due to small damping of the follower force system, known as Beck’s problem, and of the pipe conveying fluid system, two nonconservative systems, is considered. Instead of looking for a mathematical explanation, e.g. the evolution of the eigenvalues with different parameters, a more ‘physical’ explanation is provided. It is shown that it is of particular interest to focus on the different modes of vibration and to understand how they evolve when damping is varied. Also, based on energy considerations, the key factors influencing the dynamic stability are highlighted, e.g. the phase angles between the different coordinates. In the case of the pipe conveying fluid, the methodology developed and insight gained help explain the presence of ‘jumps’ in the stability curves, that are known to play an important role in the linear and nonlinear dynamics of this system.
Effect of Tube-to-Tube Ties on Fluidelastic Instability of Tube Arrays Exposed to Crossflow
Authors: Eisinger Frantisek L. , Rao Madhava M. 
Published: March 2022

Abstract
Tube-to-tube ties and their arrangement within the tube array are shown to affect the onset of fluidelastic instability. The influence of tie arrangement for a single tube row and for an in-line tube array is obtained by numerical simulation using S.S. Chen’s unsteady flow theory. Maps of dimensionless critical velocities for groups of tubes consisting of 2, 3, 4 and 5 tubes tied to each other are developed for several design configurations. It is shown that the stability limits can be raised by appropriate choice of tube group and tie location.
Fretting-Wear Damage of Heat Exchanger Tubes: A Proposed Damage Criterion Based on Tube Vibration Response
Authors: Yetisir M. , McKerrow E. , Pettigrew M. J. 
Published: March 2022

Abstract
A simple criterion is proposed to estimate fretting-wear damage in heat exchanger tubes with clearance supports. The criterion is based on parameters such as vibration frequency, mid-span vibration amplitude, span length, tube mass and an empirical wear coefficient.
It is generally accepted that fretting-wear damage is proportional to a parameter called work-rate. Work-rate is a measure of the dynamic interaction between a vibrating tube and its supports. Due to the complexity of the impact-sliding behavior at the clearance-supports, work-rate calculations for heat exchanger tubes require specialized non-linear finite element codes. These codes include contact models for various clearance-support geometries. Such non-linear finite element analyses are complex, expensive and time consuming. The proposed criterion uses the results of linear vibration analysis (i.e., vibration frequency and mid-span vibration amplitude due to turbulence) and does not require a non-linear analysis. It can be used by non-specialists for a quick evaluation of the expected work-rate, and hence, the fretting-wear damage of heat exchanger tubes.
The proposed criterion was obtained from an extensive parametric study that was conducted using a non-linear finite element program. It is shown that, by using the proposed work-rate criteria, work-rate can be estimated within a factor of two. This result, however, requires further testing with more complicated flow patterns.
Experimental Determination of Motion-Dependent Fluid Forces in Two-Phase Water-Freon Cross Flow
Authors: Delenne B. , Gay N. , Campistron R. , Banner D. 
Published: March 2022

Abstract
As flow-induced damage is a major concern for designers and operators of industrial heat exchangers and steam generators, some methodologies have been recently proposed to obtain a more accurate estimation of the critical flow velocity. These methodologies are based on unsteady semi-analytical models for fluid-dynamic forces, associated with dimensionless fluid force coefficients generally obtained from experiments. The present paper deals with new experiments performed on a square in-line tube bundle, subjected to two-phase water-freon cross-flow. A large range of void fractions and flow velocities has been investigated, up to fluidelastic instability threshold. Experimental results are analyzed first to derive evolution of frequency, damping ratio and tube motion amplitude evolution versus flow velocity and void fraction. Special attention is then focused on the determination of two-phase fluidelastic coefficients. Either homogeneous, slip or drift-flux models are used to describe two-phase flow characteristics and to dimensionalize the fluidelastic force coefficients. As a final step, the two-phase fluidelastic coefficients are compared to previously published data.
Improved Estimation of Fluidelastic Instability Threshold for Tube Arrays in Two-Phase Flow: Approximate Theory Based on Energy Balance in a Separated Flow Model
Authors: Nakamura Tomomichi , Kusakabe Takaya , Nishikawa Hideo 
Published: March 2022

Abstract
The stability boundary of tube arrays subjected to liquid-gas two-phase flow is usually estimated by a criterion similar to that for single-phase flow based on Connors’ equation. However, it has been revealed that two-phase flow instability is much more complex in our previous paper, where there exists two types of instability, intermittent instability and absolute instability.
Our theory is based on the assumption that the two phases liquid-phase and gas-phase can be separated on average. In this meaning the model is called a “separated flow model.” For each fluid phase, the energy balance between the excitation energy by fluid flow and the dissipation energy by tube vibration itself is estimated. By equating these two quantities (on average) the instability boundary is determined.
The flow distribution along the tube axis is not usually uniform. In our previous work this distribution effect was not considered. In this paper, our theory based on the energy balance in each separated flow component is expanded to include the flow-distribution effect along the tube axis.
Finally, a new criterion is for use at the practical design stage is formulated. An example showing comparison between the new criterion and the “Connors’ type formulation” is also presented.
A Theoretical Model for the Nonlinear Planar Motions of Rotors Under Fluid Confinement
Authors: Antunes José , Mendes Jorge , Grunenwald Thierry 
Published: March 2022

Abstract
In previous papers (Axisa & Antunes 1992, Antunes et al. 1996) the authors presented simplified theoretical models for both centered and eccentric immersed rotors, under moderate confinement (with reduced gaps δ = H/R of about 0.1, where H is the annular fluid gap and R is the rotor radius). In those papers rotor dynamics were modeled using linearised flow equations on the gap-averaged fluctuating quantities. Such simplified models enabled us to predict with reasonable success the modal parameters of the coupled system and the stability boundaries, as a function of the annulus geometry and rotor spinning velocity.
However, experiments have shown a progressive deterioration of the theoretical predictions at high spinning velocities as well as at large eccentricities. Such deterioration might be due to nonlinear effects which became significant near and beyond the stability boundaries. Hence, better predictions might be produced if the nonlinear terms of the flow equations were fully accounted — an issue which is pursued in this work. Because such nonlinear analysis is quite involved, this paper will focus on the simpler case of planar motions, in order to emphasize the main aspects of our approach.
A direct integration of the continuity and momentum equations leads to extremely lengthy formulations, which are very difficult to manipulate — even using symbolic computational tools. In this paper we discuss several strategies to obtain approximate solutions of the flow equations. Then we proceed with the actual approach used, which consists on the exact integration of the continuity equation and an approximate solution of the momentum equation, based on a Fourier representation of the azimuthal pressure gradient. We then obtain an exact formulation for the dynamic flow force.
The solution thus obtained is discussed in connection with physical phenomena. Numerical simulations of the nonlinear system dynamics are presented, which display interesting features. The linearised and the fully nonlinear models produces very similar results when the eccentricity and the spinning velocity are low. However, if such conditions are not met, the qualitative behavior stemming from these models is quite distinct. Experimental results indicate that the nonlinear flow model leads to better predictions of the rotor dynamics when the eccentricity is significant, when approaching instability and for linearly unstable regimes.
Hydroelastic and Vibroacoustic Behavior of Shells of Revolution
Authors: Berot François , Peseux Bernard 
Published: March 2022

Abstract
We propose two numerical models which couple the Finite Elements Method to the Boundary Elements Method. These models are designed to study the hydroelastic or vibroacoustic behavior of shells of revolution immersed in an unbounded fluid. The axisymmetric thin shell is idealized into two-node conical Ring Finite Elements. The Boundary Integral representation of the unbounded exterior fluid is discretized in two ways. The first approach uses a plane panel Boundary Element to idealize the solid-fluid interface. This quadrangular element supports constant densities of singularities. The second solution has led us to develop new Ring Boundary Elements. These elements are similar to Ring Finite Elements and make it possible to model a section of the fluid-structure interface. In this formulation, the densities of singularities are expanded in Fourier series of the circumferential variable. The coupling of Ring Finite Elements and Ring Boundary Elements widely reduces the classical numerical difficulties associated to coupled problems such as important CPU time and large storage memory.
Aeroelastic Analysis of a Trimmed Generic Hypersonic Vehicle
Authors: Nydick Ira , Friedmann Peretz P. 
Published: March 2022

Abstract
The aeroelastic equations of motion governing a hypersonic vehicle in free flight are derived. The equations of motion for a translating and rotating flexible body using Lagrange’s equations in terms of quasi-coordinates are presented. These equations are simplified for the case of a vehicle with pitch and plunge rigid body degrees of freedom and small elastic displacements. The displacements are approximated by a truncated series of the unrestrained mode shapes, which are obtained using equivalent plate theory. Subsequently, the nonlinear equations of motion are linearized about the trimmed vehicle state in horizontal flight. Unsteady aerodynamic loads for the vehicle and the appropriate stability derivatives are calculated from piston theory. The methodology for calculating the aeroelastic stability boundaries is also described. Numerical results are currently being generated.
Re-Engineering of an Aeroelastic Code for Solving Eigen Problems in All Flight Regimes
Authors: Lesoinne Michel , Farhat Charbel 
Published: March 2022

Abstract
We describe a new method for computing an arbitrary number of eigen solutions of a given aeroelastic problem. The proposed method is based on the re-engineering of a three-way coupled formulation previously developed for the solution in the time domain of nonlinear transient aeroelastic problems. It is applicable in subsonic, transonic, and supersonic flow regimes, and independently from the frequency or damping level of the target aeroelastic modes. It is based on the computation of the complex eigen solution of a carefully linearized fluid/structure interaction problem, and relies on the inverse orthogonal iteration algorithm. We illustrate this method with the stability analysis of a flat panel with infinite aspect ratio in supersonic airstreams and the AGARD 445.6 aeroelastic wing. For these aeroelastic problems, we show that the results produced by the proposed eigen solution method are in excellent agreement with those predicted analytically and numerically as well as with experimental data.
Numerical and Experimental Analyses of Segmented Modal Sensors
Authors: Sumali Hartono , Cudney Harley H. , Meissner Karsten 
Published: March 2022

Abstract
This paper presents results of numerical and experimental analyses to verily a new method to create modal sensors. A modal sensor is created by using rectangular segments of piezoelectric film and multiplying the segment outputs by certain gains so that the weighted combinations of the outputs approximate modal coordinates (Sumali and Cudney, 1993).
The method is tested on a beam with simple boundary conditions. The beam is covered with segments of piezoelectric film. It is shown that combining the outputs from the segments with correct weights results in a sensor that is sensitive to only a selected vibration mode of the beam and filters out other modes.
MEMS-Based Control of Structural Dynamic Instability
Authors: Chase J. Geoffrey , Yim Mark , Berlin Andrew A. , Maclean Brian. J. , Olivier Marc , Jacobsen Stephen C. 
Published: March 2022

Abstract
This paper describes the design, analysis and characterization of a prototype active column that applies distributed MEMS technology to a relatively new and technically challenging problem in smart structure design: the active stabilization of a buckling compressive member. The axial load bearing capacity of structural members can be increased by actively controlling the dynamic instability of buckling. Effective active stabilization is dependent on three primary factors: sensor precision, actuator authority, and control system bandwidth. A networked array of MEMS sensors, filamentary PZT actuators, and recently developed optimal control strategies are combined to demonstrate active control of an inherently unstable column. The active system, designed and simulated using finite element and optimization methods, stabilizes the column for compressive axial loads up to 2.94 times the critical buckling load. Additionally, the system is stable for all loads in the range from tension to this maximum compressive axial load.