bluuebunny/crossref_metadata_2025_split huggingface dataset:
Can Computational Goals Inform Theories of Vision?
Authors: Anderson Barton L. 
Published: March 2015

AbstractOne of the most lasting contributions of Marr's posthumous book is his articulation of the different “levels of analysis” that are needed to understand vision. Although a variety of work has examined how these different levels are related, there is comparatively little examination of the assumptions on which his proposed levels rest, or the plausibility of the approach Marr articulated given those assumptions. Marr placed particular significance on computational level theory, which specifies the “goal” of a computation, its appropriateness for solving a particular problem, and the logic by which it can be carried out. The structure of computational level theory is inherently teleological: What the brain does is described in terms of its purpose. I argue that computational level theory, and the reverse‐engineering approach it inspires, requires understanding the historical trajectory that gave rise to functional capacities that can be meaningfully attributed with some sense of purpose or goal, that is, a reconstruction of the fitness function on which natural selection acted in shaping our visual abilities. I argue that this reconstruction is required to distinguish abilities shaped by natural selection—“natural tasks” —from evolutionary “by‐products” (spandrels, co‐optations, and exaptations), rather than merely demonstrating that computational goals can be embedded in a Bayesian model that renders a particular behavior or process rational.
Use of enoxaparin in dogs with primary immune‐mediated hemolytic anemia: 21 cases
Authors: Panek Cynthia M. , Nakamura Reid K. , Bianco Domenico 
Published: March 2015

AbstractObjectiveTo describe the complications and frequency of thrombosis associated with the use of enoxaparin, a low molecular weight heparin, in dogs with primary immune‐mediated hemolytic anemia (IMHA).DesignRetrospective case series.SettingTwo privately owned veterinary referral hospitals.AnimalsTwenty‐one client‐owned dogs with primary IMHA.InterventionsDogs were treated with enoxaparin (0.8 mg/kg subcutaneously every 6 h) as the sole anticoagulation therapy starting at admission to the hospital.Measurements and Main ResultsOnly 2 dogs had minor hemorrhagic complications associated with enoxaparin therapy. Frequency of thrombosis was not assessed. Long‐term survival was comparable to other anticoagulation protocols reported for dogs with primary IMHA.ConclusionsThe use of enoxaparin was safe in a small group of dogs with primary IMHA. Whether enoxaparin therapy can reduce mortality and thrombotic complications in dogs with primary IMHA compared with other anticoagulation protocols remains unknown.
Evaluation of Electronic Prescription Implications in Turkey: An Investigation of the Perceptions of Physicians
Authors: Gіder Ömer , Ocak Saffet , Top Mehmet 
Published: March 2015

ABSTRACTBackgroundElectronic prescribing (e‐prescribing) is an evolving area of healthcare information technology that aims to support physician decision‐making by capturing, reviewing, and issuing medical prescriptions with high potential for improving the quality and safety of the process.PurposeTo describe physician perception of e‐prescription use in healthcare organizations that work with social security and to evaluate their infrastructures for MEDULA (an information system for billing and other health informatics) in healthcare organizations in Turkey.MethodsA cross‐sectional survey design was used for this study. A convenience sample of physicians in eight general hospitals and in two oral and dental health centers of the Ministry of Health in Turkey were surveyed.ResultsSurvey response rate was 47% (248/425). The majority of physicians (62%) support e‐prescribing but have not used an electronic signature for prescriptions (78.2%). Almost half of them believe that e‐prescriptions would positively contribute to patient safety (43%)Linking Evidence to ActionOur study provides a first look at the perceptions of physicians regarding the implications of e‐prescriptions, which became mandatory on January 15, 2013, in Turkey. Advocates of e‐prescribing have suggested that additional efforts are needed to strengthen clinical decision systems. Physicians and nurses are better able to adopt e‐prescribing systems and to view them positively if they recognize the limitations of paper‐based prescribing and understand the utility of electronic systems in addressing some of these limitations. This study represents a starting point for government and related organizations to improve their knowledge on how well the implied benefits of e‐prescriptions are realized in their acquisition, appraisal, and use in health policy decision‐making and health systems.
Systematic Review of Medical Home Models to Promote Transitions to Primary Adult Health Care for Adolescents Living With Autism Spectrum Disorder
Authors: Rogers Kathleen , Zeni Mary Beth 
Published: March 2015

ABSTRACTBackgroundThere is a growing number of children diagnosed and living with autism spectrum disorders (ASDs) in the United States. This increasing incidence and prevalence of ASDs require care coordination within a medical home model, which needs to continue into adulthood.AimThis paper is an evidence review of medical home models for transitioning adolescents living with ASDs from pediatric primary healthcare practices to adult primary care practices.MethodDatabases were reviewed and articles selected based on inclusion and exclusion criteria.ResultsNine articles were reviewed and four met criteria. None of the articles addressed medical home models to transition adolescents living with ASDs into adult primary healthcare services.Linking Evidence to ActionThere is a need for nursing to work within an interdisciplinary framework to educate adult healthcare providers on the needs of adolescents living with ASDs and to evaluate medical home transition models for this vulnerable population.
Crashworthy Landing Gear Design Using a Composite Tube by Extra Energy Absorber
Authors: Kim Tae-Uk , Kim Sung Joon , Lee Seunggyu 
Published: March 2015

Landing gear is the one of the key components for improving aircraft crashworthiness because its primary function is the energy absorption. But, in general, the shock absorbers are designed to have best efficiency for normal landing cases and can be ineffective when faced with very high sink speed. Thus special design and implementation are necessary for landing gear to have crashworthiness. For this purpose, various concepts have been studied and put to practical use such as structural pin, pressure relief valve and additional energy absorbing devices, etc. In this paper, the composite tube is investigated as an extra energy absorber and adopted to landing gear to increase shock absorbing performance in case of crash. To do this, first the quasi-static and impact test of composite tubes are conducted and the analysis model is tuned to explain the test results. During the correlation process, the failure modes and the specific energy absorption of the composite tubes are analyzed and the optimal configurations are searched.
The overall performance of landing gear including the composite tube is analyzed by developing a simplified dynamic model. Each force-stroke relation of oleo-pneumatic shock absorber, tire and composite tube are modeled as spring and damper, then the equation of motion is solved to obtain the crash responses. In this model, after the bottoming of shock absorber, the crushing of composite tube is activated for additional energy absorption. Numerical solutions show that the enhanced shock absorbing capability in case of crash when the composite tube adopted. For practical use, the landing gear performance should be verified by drop tests and this is author’s future research project.
Algorithm for Detecting and Solving the Problem of Under-Filled Pointed Ends Based on 3D Printing Plastic Droplet Generation
Authors: Prša Jelena , Irlinger Franz , Lueth Tim C. 
Published: March 2015

In this paper the problem of under-filled pointed ends is introduced and mathematically defined. To tackle this problem, we present a new algorithm that detects and fills the critical areas, which arise at the 3D printed plastic parts. While printing the contours and/or infill lines, due to the limitations based on the width of the extruded material, narrow edges and pointed ends remain improperly filled. This eventually results in 3D printed objects with the final geometry that differs greatly from the initial geometry.
This paper presents the fundamentals for solving the problem of 3D printing of geometries which contain narrow pointed ends. The critical area of the pointed ends is mathematically defined and, depending on the angle, the formulae for the calculation of under-filled and over-filled areas are given. The newly developed algorithm, based on the 3D Printing plastic droplet generation process, assures that the droplets of the repeating contours are placed at the edges of the contour-segments and by that minimises the potential under-fills. Furthermore, an additional number of droplets is defined, that are either printed in or removed from the under-filled areas in the angle bisector.
The proposed algorithm is applied on parts, whose geometry describes pointed ends. The final 3D printed parts are very appealing and their shape resembles the original geometry more than the final shape of the parts without applying the algorithm.
Speed Function Effects in Electron Beam Additive Manufacturing
Authors: Cheng Bo , Price Steven , Gong Xibing , Lydon James , Cooper Kenneth , Chou Kevin 
Published: March 2015

In this paper, the process parameter effects on the thermal characteristics in powder-bed electron beam additive manufacturing (EBAM) using Ti-6Al-4V powder were investigated. The machine-specific setting, called “speed function” (SF) index that controls the beam speed and the beam current during a build, was utilized to evaluate the beam scanning speed effects. EBAM parts were fabricated using different levels of SF index (20 to 65) and build surface morphology and part microstructures were examined. A near infrared (NIR) thermal imager was used for temperatures measurements during the EBAM process. In addition, a thermal model previously developed was employed for temperature predictions and comparison with the experimental results.
The major results are summarized as follows. The SF index noticeably affects the thermal characteristics in EBAM, e.g., a melt pool length of 1.72 mm vs. 1.26 mm for SF20 and SF65, respectively, at the 24.43 mm build height. This is because the higher the speed function index, the higher the beam speed, which reduces the energy density input and results in a lower process temperature. For the surface conditions and part microstructures, in general, a higher SF index tends to produce parts of rougher surfaces with more residual porosity features and large β grain columnar widths.
Influence of Geometrical Parameters on the Maximum Deep Drawing Height of Rectangular Parts
Authors: Menchi Aarón Rivas , Medellín Castillo Hugo I. , de Lange Dirk F. , García Zugasti Pedro de J. 
Published: March 2015

The deep drawing process is commonly used in the industry because its ability to produce parts with reduced weight and good mechanical properties at a high production rates. However, the elasto-plastic deformation mechanism of deep drawing is complex and difficult to analyse; this because there are many process parameters and variables involved that affect the quality of final products. Among these variables are the geometric parameters, which have been proved to have a great influence on the process. Theoretical and experimental analyses reported in the literature have been mainly focused on conventional cylindrical cup deep drawing. Few research works have dealt with the deep drawing analysis of non-cylindrical parts, particularly the influence of geometrical parameters on the deep drawing performance.
This paper presents an analysis of the effect of geometrical parameters on the allowable deep drawing height (DDH) of rectangular parts before fracture. The aim is to identify the influence of the main geometrical parameters on the DDH, Numerical analyses based on the Finite Element Method (FEM) were used to investigate the influence of geometrical parameters, such as the radii, the metal sheet thickness, and the aspect ratio, among others, on the DDH.
Load Detection and Fatigue Health Monitoring Equipment Design for Landing Gears
Authors: Jiménez Andrés , Novillo E. , Morante E. , Chamorro E. 
Published: March 2015

The Weight on Wheel system on an aircraft gives an indication of whether the aircraft has weight on its wheels, meaning the airborne is on the ground.
This system monitors the loads appearing on each Landing Gear structure. It sends a status signal to Landing gear computer that manage the redundant signals coming from each WOW systems. The management of these signals gives the information needed to activate “on ground” configuration of aircraft for braking control laws. “On ground” configuration specifies maximum load conditions and requirements for shock absorbers design for each type of aircraft (heavy freighters, military transport …)
Based on CESA experience on this field, a new approach oriented to fatigue health monitoring, is presented here. Current WOW system could be modified allowing a continuous monitoring of loads experienced by Landing Gear structure. This will optimize the life cycle of the aircraft by checking individually the status of different structural parts of each Landing Gear. Therefore, it will improve maintenance actions that will be performed only when needed. Load detection and monitoring of landing gears provides a valuable and useful information data to predict accurately the accumulated fatigue damage on landing gear components.
“Cut-Glue” Approximation in Problems on Static and Dynamic Mathematical Model Development
Authors: Neydorf Rudolf 
Published: March 2015

The solution to the problem on building mathematical models of technical objects through the approximation of various experimental dependences is offered in the paper. This approach is especially true for modeling aircraft because the aerodynamic coefficients of their models can be obtained either by full-scale study or by computer simulation only. Currently, the experimental simulation is performed either through the regression analysis (RGA) methods, or through spline approximation. However, the RGA has a significant disadvantage, namely a poor approximability of piecewise and multiextremal dependencies. The RGA gives a rough approximation of the experimental data for similar curves. Spline approximation is free from this disadvantage. However, a high degree of discretization, a strict binding to the number of spline points, and a large number of equations, make this approach inconvenient for application when a compact model building and an analytic transformation are required.
A problem solution combining the advantages of both approaches and clearing up the troubles is offered in the paper. The proposed approach is based on the regression construction of the mathematical models of the dependence fragments, the multiplicative excision of these fragments in the local functional form, and on the additive combining of these local functions into a single analytic expression. The effect is achieved by using special “selection” functions multiplicatively limiting a nonzero definition domain for each of the approximating functions. The method is named “cut-glue” by the physical analogy of the approximation techniques. The order and structure of the approximating function for each segment can be arbitrary. A significant advantage of the “cut-glue” approximation is in a single analytic expression of the whole piecewise function instead of a cumbersome system of equations. The analytical and numerical studies of the properties and operational experience of the proposed method are resulted.
The Dependence of 3D Surface Roughness Parameters on High-Speed Milling Technological Parameters and Machining Strategy
Authors: Torims Toms , Logins Andris , Rosado Pedro Castellano , Gutiérrez Santiago , Torres Rafael 
Published: March 2015

High-speed milling is an effective machining method extensively used in modern material processing. This machining method offers increased efficiency, quality and accuracy of the machined surface as well as considerably reducing overall production costs and machining time. This paper outlines comprehensive research into the impact of the technological strategy and processed materials on carefully selected 3D surface roughness parameters. This research provides manufacturers who use high-speed milling with recommendations on how to better obtain the desired surface roughness parameters. More specifically, it covers multifactorial analysis of the following factors: feed rate, manufacturing strategy, overlap and material influences on the most characteristic 3D surface parameters. The results are based on ANOVA – analysis of variance, where differences between groups of means are analysed using a range of statistical models.
Subsequent analysis and respective conclusions identify the most significant factors as being the material and high-speed milling manufacturing strategy. Analytically justified recommendations for manufacturers regarding the preferred high-speed milling strategies are provided.
The research concluded that the values of the selected 3D surface roughness parameters in high-speed milling depend significantly on the type of material being machined, milling mode and cutting tool overlap as well as feed. In particular, Sa - the arithmetic mean height, is highly sensitive to the milling mode.
Multi-Layer Computational Modeling of Selective Laser Sintering Processes
Authors: Moser Daniel , Fish Scott , Beaman Joseph , Murthy Jayathi 
Published: March 2015

Selective laser sintering (SLS) is an additive manufacturing technique able to rapidly create parts directly from a CAD model using a laser to selectively fuse successive layers of powder. However, defects can arise in SLS parts due to incomplete fusion of the powder layers or thermal stresses introduced by large temperature gradients during the part build. Accurate models of the SLS process are needed to ensure that high quality parts are produced and to allow new materials and designs to be used without requiring extensive experimentation. Most existing models of the SLS process are very narrowly focused, predicting the temperature history of a single powder layer after a single laser pass or examining the impact of a few processing parameters on the properties of the produced part. A model capable of predicting a complete temperature history during an entire part build does not yet exist. Therefore, a new thermal model able to simulate multiple powder layers is proposed.
A transient, three-dimensional, finite volume model is developed and implemented in ANSYS Fluent. A domain of cells representing multiple layers of an SLS build is initialized, some with the properties of air and some with the properties of powder, depending on cell location. A Gaussian heat source representing the laser is applied to the top layer of powder cells. The center of the Gaussian is varied with time along an established path to simulate the motion of the laser along the powder bed. At all times the three-dimensional heat equation is solved to produce a temperature profile of the powder bed. When the laser completes a full scan of the powder layer, the air cells directly above the powder layer are re-initialized as powder cells and re-set to an initial temperature, representing the addition of a new powder layer. The process is repeated for each new layer. Temperature history results from the model are validated against experimental data available in the literature and good agreement is obtained. As the model accounts for multiple powder layers, it can be used to simulate an entire part build and predict the impact of any of the SLS processing parameters on part quality and thus enable better control and optimization of the SLS process.
Working Load Analysis and Strength Estimation for Bolted Joints During Actual Machine Operation
Authors: Hareyama Soichi , Manabe Ken-ichi , Shimodaira Takayuki , Hoshi Akio 
Published: March 2015

Serious problems caused by bolted joint fatigue breakage still occur. This is because working load evaluation and durability strength evaluation have been insufficient in the product design stage, in the test stage of machine lifetime prediction, in the trial production stage, in the prototype machine test stage, and so forth.
In this paper, we propose a method for measuring and analyzing the load on bolted joints used in a machine under actual operation. Working load measurement under actual machine operation and the results of its analysis are shown as load frequency diagrams. This is very important information for realizing the concept of simultaneous multiple design. An example of the measurement analysis method of the load (three types of the loads; axial force, bending moment, and the torsional torque) added to the bolted joint shank which comes out at the time of the actual machine operation is shown.
The reliability of assessing the strength and durability of bolted joints is considered from the viewpoint of limited-lifetime (finite-lifetime) design using Miner’s rule with cumulative loosening damage models and fatigue limit (infinite-lifetime) design. As an example, we measured the working stress and evaluated the strength of a bolted joint of an actual machine to verify the usefulness of the proposed method. Also, examples of strength evaluation are shown to illustrate finite-lifetime and infinite-lifetime prediction.
Moreover, the practical process and presumed example of fatigue life prediction are shown. It is considered as a contribution at the improvement of strength reliability and the load analysis method of the bolted joint of machine develop-ment stage and failure analysis stage. Our findings are also expected to eradicating accidents involving bolted joints in machines.
Design and Analysis of a Highly Loaded Tandem Compressor Stage
Authors: Eshraghi Hamzeh , Boroomand Masoud , Tousi Abolghasem M. 
Published: March 2015

In this study, a 3D design procedure for axial flow tandem stage is developed, and then a highly loaded stage is designed with this method. Designed stage is numerically investigated with a CFD code and the stage characteristic map is reported. In order to investigate the effect of highly loaded design, a conventionally loaded compressor stage is designed with single blade for rotor and stator rows. For a better comparison, Chord lengths and hub/shroud geometries are selected same between highly and conventionally loaded compressors. Characteristic map of the conventional compressor is reported too and performance of highly loaded and conventionally loaded compressors are compared.
To validate the CFD method, another compressor stage is presented that its geometry and experimental results are available. Performance of the recent compressor stage is numerically investigated and compared with experimental results.