bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance Determination of Axial Wind Tunnel Fan With Reverse Engineering, Numerical and Experimental Methods
Authors: Kocak Eyup , Ayli Ece 
Published: January 2022

Abstract
In today’s technology, in case of the need for rehabilitation, renovation, or damage, it is necessary to recover the problems quickly with a cost-effective approach. In the case of destructive failure, or misdesign of the devices, replacing the problematic part with the new design is crucial. In order to substitute the related part with the efficient one, reverse engineering (RE) methodology is utilized. In this paper, from the perspective of engineering implementation and based on the idea of reverse engineering, axial wind tunnel fan is rehabilitated using numerical and experimental methods. The current study is focused on an axial pressurization fan placed into Cankaya University Mechanical Engineering Laboratory wind tunnel that has firm guaranteed specifications of 5.55 m3/s airflow capacity. The measurements performed during experiments showed that the fan provides less than 60% airflow compared with firm guaranteed specifications. In order to determine the problems of the existing fan, a reverse engineering methodology is developed, and the noncontact data acquisition method is used to form a computer aided drawing (CAD) model. A computational fluid dynamics (CFD) methodology is developed to analyze existing geometry numerically, and results are compared with an experimental study to verify numerical methodology. According to the results, the prediction accuracy of the numerical method can attain 92.95% and 96.38% for flowrate and efficiency, respectively, at the maximum error points.
Computational and Experimental Analysis of Hemodialysis Catheters
Authors: Siegel J. M. , Raghavan J. , Lei M. , Abraham T. , Makhijani V. B. 
Published: January 2022

Abstract
Hemodialysis catheters are primarily used in instances of acute renal failure and poisonings. The typical hemodialysis catheter consists of a polymer tube with either single or double lumen. The tube is inserted into one of three preferred catheter access sites: the femoral vein, subclavian vein, or internal jugular vein. Once in place, the catheter is available for vascular access during hemodialysis. Despite advances in hemodialysis catheter design, a multitude of problems still exist. Venous access thrombosis and stenosis distal to the catheter outlet port are common. Unacceptable levels of recirculation (filtered blood returning to the catheter inflow port) are often observed in these catheters. The purpose of this study is to analyze the effects of different catheter design parameters on the reduction of access recirculation, maximum fluid shear rate and pressure drop across the device.
Viscoelastic Finite Element Contact Analysis of Articular Joints
Authors: Yu Hongrong , Stone James J.-S. 
Published: January 2022

Abstract
Joint contact analysis of the musculoskeletal system is one of the important biomechanical research topics due to its significant clinical relevance. The articular cartilage and its mechanical behavior play a key role in the articular joint contact. Articular joint models considering the time-dependent viscoelastic properties of cartilage, and joint congruences were studied. Results of the maximum normal contact stresses and related contact region versus time for two-dimensional plane stress and three-dimensional axisymmetric cases are presented.
Comparative Assessment of Dynamic Rotational Stiffness of Common and Prototype Foot/Ankle Prosthesis During Simulated Stance
Authors: Quesada Peter M. , Pitkin Mark , Colvin Jim , Hays John 
Published: January 2022

Abstract
Dynamic rotational stiffnesses during simulated stance phase dorsiflexion were experimentally determined for six variants of rolling joint foot/ankle (RJFA) prosthesis prototypes, and five commercially available foot/ankle components (College Park, Seattle, Endolite, Flex Foot and single axis). The lowest stiffnesses, during the first half of simulated stance phase dorsiflexion, were exhibited by three of the RJFA variants. Additionally, these variants’ stiffnesses during first half stance dorsiflexion were lower than their respective stiffnesses during second half stance dorsiflexion. Conversely, only one of the commercially available components (single axis foot), displayed this dynamic stiffness behavior. These RJFA variants’ responses, which more closely mimic that of the anatomic ankle, may function to lessen stance phase transmission of loads from socket to residual limb. Greater stance phase knee flexion and earlier foot flat may also be possible and could lead to better shock absorption, lower energy cost, and improved stability.
Regularization Matrices for Inverse Electrocardiography
Authors: Olson Lorraine G. , Throne Robert D. 
Published: January 2022

Abstract
In a recent series of papers we proposed a new class of methods, the generalized eigensystem (GES) methods, for solving the inverse problem of electrocardiography. In this paper, we compare zero, first, and second order regularized GES methods to zero, first, and second order Tikhonov methods.
Results from higher order regularization depend heavily on the exact form of the regularization operator, and operators generated by finite element techniques give the most accurate and consistent results. The GES techniques always produce smaller average relative errors than the Tikhonov techniques, but as the regularization order increases the difference in average relative errors between the two techniques becomes less pronounced.
Control and Pattern Specification for a High Density Tactile Array
Authors: Pawluk D. T. V. , van Buskirk C. P. , Killebrew J. H. , Hsiao S. S. , Johnson K. O. 
Published: January 2022

Abstract
In this paper we discuss the control and spatiotemporal pattern specification for a high density tactile display. The display consists of a configuration of 400 probes applying approximately normal forces to the contact surface. Except for horizontal skin stretch, the device is designed to be capable of simulating most psychophysically and physiologically relevant spatiotemporal patterns. It also is capable of providing a high resolution test-bed for tactile rendering algorithms for haptic interfaces.
Photodeformation Based Optomechanical Shell Actuators Applied to Vibration Control of Continua: A Sensitivity Study
Authors: Liu B. J. , Kidd D. , Tzou H. S. 
Published: January 2022

Abstract
Photodeformation involves two fundamental opto-electromechanical coupling phenomena: 1) the photovoltaic effect and 2) the converse piezoelectric effect. Irradiating high-energy lights, such as lasers or ultraviolet lights, on certain classes of photostrictive materials can trigger the photodeformation process and the induced strains can be used for non-contact precision actuation and control. This paper is to evaluate the sensitivity and the distributed control effectiveness of distributed optomechanical shell actuators. Various design parameters, e.g., in-plane and out-of-plane control actions, actuator sizes and locations, are evaluated and their sensitivities are reported.
Experimental Hybrid Active Vibration Control of a Cable-Stayed Bridge
Authors: Bell Mark J. , Shoureshi Rahmat 
Published: January 2022

Abstract
The focus of this paper is active vibration control with application to cable-stayed bridges. Hybrid vibration control, involving the combined use of feedforward and feedback action, is applied to a prototype cable-stayed bridge. The control objective is to reject all disturbances that produce unwanted motion in the bridge structure, namely seismic activity, wave loading and wind loading. A 1/150 scale model of a cable-stayed bridge is designed and fabricated from steel, aluminum, and steel wire and compared to an existing structure using experimental modal analysis. A three-dimensional finite element model of the bridge is developed for verification purposes. The frequency range of interest for the structural active vibration control problem is determined, A method for placing sensors and actuators on the structure is developed using operational vibration data within the frequency range of interest. An adaptive, combined feedforward and feedback control system is implemented on the structure.
Noise Generation due to Turbulent Flow Over Surface Slots
Authors: Grega Lisa M. , Farabee Theodore M. , Wei Timothy 
Published: January 2022

Abstract
An experimental investigation was conducted which addressed noise generation mechanisms due to turbulent boundary layer flow over a series of surface slots. The objectives of the experiment were to identify localized radiated noise sources from the slots and to relate these noise sources to interactions between near-wall turbulent boundary layer fluid and the slots. Radiated noise from an assembly of angled slats mounted in a flat plate was measured under various inflow boundary layer conditions, which were quantified from mean streamwise velocity measurements. In addition, higher order turbulence statistics were provided by high resolution DPIV measurements made at Rutgers University. Results of the radiated noise studies indicated that noise generated due to turbulent flow over the slats scaled with outer flow variables and that this noise was predominantly produced from the forward half of the slat assembly. Based on the flow measurements, it is believed that this effect is due to increased near-wall velocities in the forward half of the slat assembly, resulting in stronger interactions between near-wall fluid and the slats and ultimately increased Reynolds stress gradients.
Effects of Bulk Flow Pulsation on Film Cooling
Authors: Chyu M. K. , Yen C. H. , Shih T. I.-P. 
Published: January 2022

Abstract
Described in this paper is an experimental investigation on the effects of flow pulsation on both the film effectiveness and heat transfer coefficient in the vicinity of a row of five injection holes with a 30° inclination relative to the mainstream direction. The experiment uses a transient liquid crystal technique designed for studies of three-temperature convection systems. Generation of pulsation in the mainstream uses a rotating shutter attached at the downstream end of the test channel, which produces a sinusoidal disturbance in both static pressure and mean velocity. The experiment conducted covers a range of Strouhal numbers from 0 to 0.6 and blowing ratios from 0.3 to 1.0, while the Reynolds number is maintained constant at approximately 2,770. The results show that the presence of flow pulsation significantly reduces the magnitudes of film effectiveness. On the other hand, the values of convective heat transfer coefficient appear to increase with the Strouhal number. However, the local heat transfer coefficient immediately downstream to the injection hole is somewhat insensitive to the level of pulsating disturbance.
A 2-D Numerical Model for Flow Simulation in Radial Turbomachineries
Authors: Sadeghipour Sadegh M. , Najafi Amir F. 
Published: January 2022

Abstract
In this investigation a computer code has been developed to simulate fluid flow in radial turbomachineries. The ARDC2D Euler code has been used as the base code. This is a two dimensional finite difference code based on the Beam-Warming implicit method which solves compressible external flows.
The code has been modified to simulate internal flows and to take into account the effect of the control volume rotation.
The modified code was first verified by simulating the air incompressible flow in a rotating channel for which analytical solution exists. Then, it was used to simulate the air incompressible flow in a radial fan.
Analysis of the Relation Between Exergy and Enthalpy and Their Derivatives for Superheated Steam
Authors: Llagostera Jorge 
Published: January 2022

Abstract
A thermodynamic relation, defined to improve methodologies in the Second Law Analysis of thermal systems, is studied. This relation is defined by dividing the specific thermomechanical exergy by the specific enthalpy of a substance, adopting as reference a selected thermodynamic state. This relation is determined and analyzed for liquid water and steam in a range of temperatures (30°C – 700°C) and pressures (0.101325 MPa – 18.1 MPa). The behavior of the proposed relation is compared against the exergy behavior as a function of temperature and pressure. The proposed relation can be used to compare and evaluate thermodynamic states that have similar exergy content. It makes possible the identification of states presenting higher exergetic level per enthalpy unit. The variation of partial derivatives (temperature and pressure) of the specific thermo-mechanical exergy for superheated steam is analyzed. The variation of partial derivatives of the thermodynamic relation between the exergy and enthalpy (adopting as reference a selected thermodynamic state) is also studied. These derivatives are determined for sub-cooled liquid water and superheated steam in a range of temperatures (200°C – 700°C) and pressures (2 MPa – 18 MPa). The behavior of the partial derivatives is compared and discussed against the variation of enthalpy and entropy, considering the effects of temperature and pressure variations. The analysis performed in this work can help to improve methodologies in the Second Law Analysis of thermal systems. The aspects focused upon can be useful in thermodynamic analysis and optimization of steam cycles and thermal processes.
Experimental Comparison of a Nearly Azeotropic Refrigerant Blend and R-22 in a Water-to-Water Laboratory Test Rig
Authors: Baxter Van D. , Chen Dong-Tsia , Linkous Randy L. , Nimitz Jon 
Published: January 2022

Abstract
A newly developed, non-ozone-depleting refrigerant blend containing a fluoroiodocarbon compound was compared with R-22 in a laboratory-scale, water-to-water refrigeration cycle test loop. The loop is equipped with a coaxial tube-in-tube condenser, a baffled shell-in-tube evaporator, and a variable-speed compressor. The blend and R-22 were tested at saturated evaporator temperature conditions of about −10 °F to −20 °F and saturated condenser temperature conditions from about 80 °F to 100 °F. The compressor speed was varied such that evaporator (cooling) capacity was held constant at approximately the same value for both refrigerants for each test condition. To maintain equal capacity, results showed the compressor speed for the blend to be at least 53% greater than that for R-22. Measured system efficiency with the blend was at least 25% better than for R-22 for near equal operating temperature and capacity conditions. When allowing for maximum impact of the experimental uncertainties, the minimum COP improvement observed for the blend was about 10%. Ideal cycle calculations using the best available property estimates for the blend and the compressor efficiencies observed during the tests also suggested a 10% improvement for the blend over R-22 (almost all due to better isentropic efficiency of the compressor with the blend). Better thermodynamic property data are needed for the blend and further investigations are needed to fully assess its potential for refrigeration equipment applications.
Active Vibration Abatement in a Turning Process by Applying a Magnetostrictively Actuated Tool Holder
Authors: Liu Dongming , Sutherland John W. 
Published: January 2022

Abstract
The vibration of the cutting tool in a turning process is known to have detrimental effects on the surface finish of machined parts. For a given cutting condition, better surface finish can be achieved by suppressing the vibration. In this paper, an active vibration control system for a turning process is presented. The system employs a magnetostrictive actuator to suppress the vibration caused by random excitation in the turning process. The magnetostrictive actuator and sensors are integrated into a specially designed tool holder. A model that accounts for both the dynamics of the cutting process and the tool holder is described. Based on the model, a controller is designed for the tool holder by μ-synthesis method. The effectiveness of the vibration control system is evaluated via impulse response tests and a series of cutting experiments. Frequency response results from the impulse response tests showed that the actively controlled tool holder effectively reduced the vibration of the cutting tool. In the cutting experiments with the tool holder, surface profiles with/without vibration control were collected and studied. It is shown that the system can improve the surface texture generated by the turning process.
Distributed Sensor Optimization for Fault Diagnosis in Multi-Fixture Assembly Systems
Authors: Khan Ashraf , Ceglarek Dariusz 
Published: January 2022

Abstract
Sensing for the system-wide diagnosis of dimensional faults in multi-fixture sheet metal assembly presents significant issues of complexity due to the number of levels of assembly and the number of possible faults at each level. The traditional allocation of sensing at a single measurement station is no longer sufficient to guarantee adequate fault diagnostic information for the increased parts and levels of a complex assembly system architecture. This creates a need for an efficient distribution of limited sensing resources to multiple measurement locations in assembly. The proposed methodology achieves adequate diagnostic performance by configuring sensing to provide an optimally distinctive signature for each fault in assembly. A multi-level, two-step, hierarchical optimization procedure using problem decomposition, based on assembly structure data derived directly from CAD files, is used to obtain such a novel, distributed sensor configuration. Diagnosability performance is quantified in the form of a defined index, which serves the dual purpose of guiding the optimization and establishing the diagnostic worth of any candidate sensor distribution. Examples, using a multi-fixture layout, are presented to illustrate the methodology.
Underfill Selection and its Impact on the Reliability of Flip-Chip Assemblies
Authors: Yan Xiantao 
Published: January 2022

Abstract
Underfill materials play a key role in the reliability of flip-chip assemblies on organic circuit boards. Underfill selection has great impact on the interfacial integrity, stresses in the die, and strains in the solder bump. Therefore, it is critical to optimize underfill properties for enhanced reliability of flip-chip assemblies. In this study, effect of underfill properties on interfacial integrity, stresses in the die, and strains in solder bumps is investigated using analytical and experimental methods. Interfacial fracture toughness for die/underfill and underfill/circuit board interfaces are obtained using four-point-bend specimens. Effect of underfill properties on die cracking is investigated by an analytical solution for a three-layered structure. The impact of underfill properties on maximum strains in solder joints and their implications on solder fatigue are evaluated using the moire interferometry method. Results show that a good underfill can be characterized as (a) having adequate interfacial fracture toughness at chip/underfill and underfill/circuit board interfaces, (b) minimizing strains in solder bumps, (c) not causing excessive tensile stress in the die, and (d) having fracture toughness higher or comparable to that of the interfaces. In addition to the above essential requirements, underfill should have a high glass transition temperature, good flow properties, and high moisture resistance.
A systematic review of clinical practice guidelines for childhood glaucoma
Authors: Lingham Gareth , Thakur Sahil , Safi Sare , Gordon Iris , Evans Jennifer R , Keel Stuart 
Published: January 2022

ObjectiveTo conduct a systematic review to identify and critically appraise clinical practice guidelines on the assessment, diagnosis and management of childhood glaucoma.Methods and analysisA systematic literature search of databases and professional websites for clinical practice guidelines published on eye conditions between 2010 and April 2020 in English was conducted. Identified guidelines were screened for relevance to childhood glaucoma and exclusion criteria applied. Guidelines that passed the screening and quality appraisal with the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool and, if they achieved a mean score of ≥45 and ≥3 on subsets of 9 and 5 AGREE II items, respectively, were selected for inclusion and data extracted using a standardised form.ResultsFollowing screening and critical appraisal, three guidelines were included for data extraction. None of the three guidelines was specifically developed for childhood glaucoma. A consistent recommendation was that children should undergo some form of eye screening examination or a comprehensive eye assessment to detect paediatric eye disease. Children at high risk of childhood glaucoma should undergo additional screening. One clinical practice guideline recommended interventions for childhood glaucoma consisting of tube surgery and topical beta-blockers or carbonic anhydrase inhibitors. Recommended interventions for childhood glaucoma were based on low-quality to moderate-quality evidence or expert opinion.ConclusionBased on our selection criteria, we did not identify any high-quality clinical practice guidelines specifically targeted at childhood glaucoma. This is compounded by the lack of high-quality evidence on childhood glaucoma.
Patient and family perspectives of a Pre-Transition Visit in a paediatric tertiary care diabetes clinic
Authors: Marr Alexa , Tsampalieros Anne , Courtney Jennilea , Seid Hamid Jemila , St-Denis-Murphy Josee , Stevens Liz , Ahmet Alexandra , Goldbloom Ellen B 
Published: January 2022

IntroductionThe need to better prepare youth with type 1 diabetes for the transition from paediatric to adult care is evident. As part of a regional quality improvement initiative, a novel Pre-Transition (Pre-T) Visit was developed and piloted at a paediatric tertiary care centre in January 2018 for patients aged 15–18 years to capture the status of their self-management skills, introduce transition tools and identify self-care goals and knowledge gaps to be addressed prior to transition.PurposeTo evaluate patient and family satisfaction, visit relevance and patient engagement with a novel Pre-T Visit.MethodsFrom May 2019 to March 2020 a survey was offered to all youth who attended a Pre-T Visit and their parent(s)/caregiver(s). Patient and family satisfaction with, relevance of and engagement with the Pre-T Visit were evaluated using a 5-point Likert scale. Multivariable regression was used to assess patient factors associated with patient level satisfaction.ResultsOf the 63 youth who participated in a Pre-T Visit, 60 completed the survey. Mean age (SD) of participants was 16.7 (0.8) years; 47% were female. Mean (SD) haemoglobin A1C (A1C) was 8.2% (1.8). Patients reported high levels of satisfaction (95% quite or extremely satisfied) that were consistent across age, A1C, gender and disease duration. Visit relevance and engagement were also rated highly by youth. Parent participants (n=27) also reported high levels of satisfaction (89% quite or extremely satisfied) and relevance.ConclusionsPre-T Visits were rated highly by patients and their parents. Their impact on glycaemic control and health outcomes following transition requires further study.