bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxygenation pattern and compensatory responses to hypoxia and hypercapnia following bilateral carotid body resection in humans
Authors: Niewinski Piotr , Tubek Stanislaw , Paton Julian F. R. , Banasiak Waldemar , Ponikowski Piotr 
Published: February 2021

Key points
Five years after bilateral carotid body resection (bCBR) performed in four patients, the absence of the hypoxic ventilatory response persisted, suggesting no compensatory regrowth.
Breathing hypoxic gas mixtures (15% and 12%) results in a lower (by ∼10%) minimal blood oxygen saturation () in bCBR patients compared to heart failure subjects (CHF) with intact peripheral chemoreceptors.
After bCBR, patients were characterized by a greater short‐term variability in during mild hypoxia in comparison to the CHF group.
The ventilatory response to hypercapnia was preserved following bCBR and was sufficient to maintain minimal at levels comparable to controls when combined with hypoxia.
Bilateral CBR – a novel treatment modality for sympathetically mediated diseases – should be used with caution due to the risk of significant desaturation even during mild hypoxia equivalent to that experienced during long‐haul air travel and high altitude.
AbstractCarotid body resection has been proposed as a novel treatment for sympathetically mediated diseases but the safety of bilateral carotid body resection (bCBR) for blood oxygenation during hypoxic stress (long‐haul flights or high altitude) remains uncertain. Also unknown is whether central ventilatory drive is sufficient to maintain adequate oxygen saturation when exposed to hypercapnia with concomitant hypoxia. Thus, we administered: 15% O2, 12% O2, 5% CO2/12% O2 and 5% CO2/95% O2 to a group of four patients with congestive heart failure (65 ± 2.9 years) in whom bCBR was performed 5 years earlier. Ventilatory, haemodynamic and blood oxygen saturation () responses were recorded non‐invasively and compared to control groups with intact peripheral chemoreceptors (both healthy and heart failure patients). First, we confirmed that the ventilatory response to hypoxia was eliminated in patients with bCBR, although the increase in cardiac output was preserved. Second, administration of hypoxic gas mixtures resulted in a larger decrease in and greater short‐term variability of the leading to a lower minimal for both hypoxia levels in the bCBR group compared to heart failure controls (82.5 ± 1.2% vs. 91.6 ± 2.3% for 15% O2 and 73.8 ± 4.0% vs. 83.7 ± 3.1% for 12% O2). Third, in bCBR patients the ventilatory response to hypercapnia was present and sufficient to maintain a minimal at a level comparable to heart failure controls following administration of 5% CO2/12% O2 (88.7 ± 4.2% vs. 91.1 ± 2.8%). We conclude that bCBR carries a risk of significant oxygen desaturation even during mild hypoxia. Despite preservation of central chemosensitivity, future studies should focus on unilateral CBR or on pharmacological modulation of peripheral chemosensitivity.
Feature-Based Assembly Design: Concepts and Design Environment
Authors: Bordegoni Monica , Cugini Umberto 
Published: February 2021

Abstract
The design of mechanical assemblies is mainly done after having modeled single parts. Most of the CAD systems are still weak for what concerns assembly. For example, they do not support the manipulation or the modification of the part geometry or the mating conditions once the assembly is made. The introduction of a feature-based approach in assembly design, successfully used in the design of single parts, would offer several advantages. This paper describes some results of the research work done within a project funded by the European Union aiming at extending the use of features, to help in the solution of assembly problems in the aeronautical applications.
Feature Visualization
Authors: Versluis Jan Wouter , Bronsvoort Willem F. , de Kraker Klaas Jan , Seebregts Kees 
Published: February 2021

Abstract
New techniques for visualizing feature models are presented. These do not only provide better geometric and spatial model insight than the standard display techniques, but also functional insight into a feature model by visualizing engineering information.
Geometry is visualized by combining shaded and line visualization techniques, resulting in clearer images.
Among the engineering information that is visualized are feature intersections, closure faces and feature parameters. This is done by explicitly displaying feature geometry instead of the geometry of the final shape only, and by displaying additional information in a model image.
Combined, these techniques provide powerful possibilities to visualize feature models.
The implementation uses specified feature and camera properties and a cellular geometric datastructure for generating images. The cellular data structure contains the feature geometry information required for feature visualization.
Feature Extraction and Operation Sequencing for Machining on Mill-Turns
Authors: Dutta Debaslsh , Kim Yong Se , Kim Youngjin , Wang Eric , Yip-Hoi Derek 
Published: February 2021

Abstract
An integrated system to support both product and manufacturing process design should be such that (1) the part design can be evaluated and redesigned based on manufacturability analysis and (2) the manufacturing processes can be selected efficiently and flexibly exploiting product information provided by part design representations.
In this paper, we describe the collaborative research of the University of Illinois at Urbana-Champaign (UIUC) and the University of Michigan (UM) in computer-aided process planning for mill-turn machining. The UIUC geometric reasoning system based on convex decomposition identifies the machining features and maps the negative feature volumes to machining process methods, and generates geometry-based machining precedence relations. The UM process planning system based on genetic algorithm determines machining process sequences and assignment to multiple spindles and turrets.
A Knowledge-Based Approach to Concurrent Design of Sheet Metal Forming Product and Process and its Preliminary Implementation
Authors: Yang Shiyong , Nezu Kikuo 
Published: February 2021

Abstract
This article deals with concurrent design of sheet metal forming product and process by using process modeling and knowledge-based approach. An inverse finite element algorithm and knowledge representation schemes are presented. Numeric models out of process modeling are integrated into knowledge base, with resort to a mathematical and graphical software MATLAB and to a supporting shell called “concurrent design environment” (CDE) developed in Common Lisp. The proposed system can make preliminary determination of product and process specifications such that the product is compatible with its targeted forming conditions with maximum material utilization ratio, shortest lead-time, and reliable quality.
The Application Protocol Information Base World Wide Web Gateway
Authors: Lubell Joshua 
Published: February 2021

Abstract
The Application Protocol Information Base (APIB) is an on-line repository of documents for the Standard for the Exchange of Product model data (STEP, officially ISO 10303 — Product Data Representation and Exchange). Document types in the APIB include STEP Application Protocols and Integrated Resources. Application Protocols are standards that are intended to be implemented in software systems, and Integrated Resources are used by them as building blocks. Application Protocols and Integrated Resources are represented in the Standard Generalized Markup Language (SGML) in the APIB in order to facilitate efficient information search and retrieval. This paper describes a World Wide Web gateway to the APIB, implemented using the Common Gateway Interface (CGI) standard. The APIB gateway allows STEP developers to efficiently search for ISO 10303 standards and supporting information. The only client software required to use the APIB gateway is a third party web browser.
VirTeam Tool
Authors: Hillmer Dirk 
Published: February 2021

Abstract
The rapid evolution of information and the new potentials for communication between people, have been of great importance to the success of most organizations. Key aspects were the increased availability of computer networks and the rowing trend towards team work.
People are becoming connected through the Internet. People can use the network behind their computer as a great resource for solving problems. The purpose of this research is to simplify starts of collaboration tools. Individuals will be able to establish connections on demand. The schedule of group appointments and conference schedule should be supported, therefore, all necessary information has to be provided. Also behind firewalls a secure way to allow access to these data has to be found.
A Generic Framework for Internet-Based Supply-Chain Interaction
Authors: Veeramani D. , Joshi S. M. 
Published: February 2021

Abstract
To remain competitive in the global marketplace, manufacturing companies are transforming their organizational structure and operational philosophy from one based on vertical-integration to one based on core competencies. This trend has resulted in an economy wherein practically every manufacturing company has become dependent on a supply-chain of vendors in order to serve its customers. In the context of this distributed manufacturing environment, the Internet and related technologies such as Java, VRML and intelligent WWW agents are creating fundamentally new approaches to supply-chain interactions that offer greater flexibility in identifying suppliers and the ability to dramatically reduce the response time within a supply-chain for processing requests-for-quotation (RFQs) and orders from customers. In this paper, we describe a generic framework for Internet-based customer-vendor interactions, and present a computer-integrated system for rapid and effective processing of RFQs in such an Internet-based supply-chain. We also identify some key research challenges within this framework that need to be overcome for Internet-based supply-chain interaction to be successful.
Case Studies on the Use of Virtual Reality for an Integrated Design and Manufacturing System
Authors: Angster Scott , Jayaram Sankar , Hutton David 
Published: February 2021

Abstract
Companies are being forced to create products at a highly accelerated rate and have turned to new design techniques such as virtual prototyping. One of the newest virtual prototyping tools is the use of virtual reality for design and manufacturing analysis. Many groups have developed systems that use virtual reality techniques such as virtual fly-throughs, simulations and three-dimensional visualization. Additionally, there is an increased amount of research in the area of human-integrated techniques or human-in-the-loop analysis using virtual reality. In the field of design and manufacturing, most work has either been in simulation or in the field of human interaction without the use of virtual reality. Although these provide valuable information, a system that couples human-interaction with virtual reality can provide more information than that provided by current computer-aided design and manufacturing software. One concern, however, is the accuracy of these systems and whether the data that is obtained from these systems can be utilized. This paper presents studies performed in a virtual environment for a design and manufacturing system.
Computer Aided Design of Rotary Screen and its Conveyor for Solid Waste Processing Systems
Authors: Kaftanoglu Bilgin , Alkan Okan 
Published: February 2021

Abstract
In this study, typical solid waste processing systems are analyzed. Then, a rotary screen and conveyor is designed for composting plants. A computer program is developed for the design procedure. By use of a simulation model included in the program, data are obtained and these are plotted to see system characteristics. These data then, are compared with the previous works.
Air Filter Pleat Flow Simulations With Monte Carlo Particle Deposition
Authors: Vickery Curtis M. 
Published: February 2021

Abstract
Automotive air filter pleat parameters must often be estimated by design engineers, affecting overall filter performance. This paper examines pressure-flow response of and particle deposition upon three different pleat profiles. Pleat models, analysis operating point, and analysis parameters were based on a Purolator automotive air filter application. Computational assumptions included steady state, incompressible, isothermal, laminar air flow with a modified/extended Darcy law equation used for media flow computations. Inlet velocities were set to maintain the filter rated volumetric flow rate with equal pressure drop through each pleat model.
1–50 micron diameter spherical particles were used in Monte Carlo particle deposition analyses. Once introduced into the computed flow fields, particle trajectories were computed assuming inertial, body, buoyancy, and drag forces were active. Histograms depicting particle starting and deposition locations were constructed for five particle size sub-classes. Flow field and structural influences on particle deposition tendencies were noted.
Geometric Tools Dedicated to the Adaption and Idealization of 3D Models for F.E. Analysis
Authors: Véron Philippe , Léon Jean-Claude 
Published: February 2021

Abstract
Geometric adaptions and idealizations of 3D models for F.E. analysis purposes are often necessary. Geometric tools are proposed to partly automatize shape adaptions and idealizations of polyhedral models. The simplification process is monitored using error zones attached to each polyhedron vertex. Their dimension may be either set by the designer, by an a posteriori or by an a priori mechanical mesh adaption process. Such an approach allows to process various polyhedral models characterized by general and complex shapes. A classification of nodes and edges is carried out to apply a specific node removal operator in accordance with the local geometric configuration around a node. Moreover, specific criteria are used to select the best candidate node for removal. Also, additional operators have been developed to process particular configurations and produce the final idealized model. During this geometric idealization process, the shape restitution of the part is maintained through an inheritance process of the error zones. Topological changes as well as the coherence of the non-manifold geometric model are managed using specific criteria to produce acceptable approximations of idealized geometries.
Modeling and Pressure-Based Force Control of a Hydraulic Actuator
Authors: Lyon Scott M. , Evans Mark S. 
Published: February 2021

Abstract
A dynamic model of a hydraulic actuator/spool valve combination is developed using the bond graph method. Feedback linearization is used to develop a force controller for the system using hydraulic pressure in each chamber of the actuator along with piston position and velocity as feedback. The use of a feedforward term to compensate for the seal friction within the actuator provides for a stable and accurate controller. Velocity control is achieved through calculation of the reference force required to overcome the seal friction and produce the acceleration required to reach the desired velocity. It is shown that the use of such a force controller allows for an acceptable transition from velocity to force control when the piston comes in contact with an external surface.
A Decomposition Approach for the Topological Synthesis of Articulated Gear Mechanisms
Authors: Chen Dar-Zen , Liu Chia-Pin 
Published: February 2021

Abstract
This paper presents an efficient methodology for the structural synthesis of articulated gear mechanisms. This approach is based on the idea that the kinematic structure of a articulated gear mechanism can be described by an equivalent open-loop chain and mechanical transmission lines and each mechanical transmission line by input and transmission units. A model is established to represent the hierarchical relation among subsystems. A link partition algorithm is also presented to decompose the constraints on the number of link in the decomposition process. According to the model and partition algorithm, a composition polynomial is derived to represent the typology decomposition relation within the desired mechanism with specified configuration and number of links. In the composition polynomial, subsystems in each level are defined symbolically with the distributed number of links and configuration. From the unit-level composition polynomial, unit combinations of the desired mechanism are indicated. Thus, suitable units can be selected from the former identified admissible units and combined upward along the hierarchical model according to the synthesis process. With the clear specification on the composition of the desired mechanism, admissible mechanisms can be enumerated efficiently and systematically.
Finding the Principal Axes of Screw Systems
Authors: Parkin Ian A. 
Published: February 2021

Abstract
The paper provides computational methods for determining the principal screws of an N-system of screws of the form S^=∑i=1NaiS^i,aireal when a basis of N, 2 ≤ N ≤ 5, linearly independent screws Ŝi has been provided.
Trimmed Free-Form Surfaces Submitted to Parametric Modelling
Authors: Guillet Stéphane , Léon Jean-Claude 
Published: February 2021

Abstract
A new parametric modelling approach focusing on trimmed free-form surfaces is introduced. The surface deformation process required is controlled through geometric constraints such as deforming the surface until it becomes tangent to a pre-defined plane.
Surfaces are bounded by trimming lines and use a multi-patch representation (i.e.: a B-Spline based model). The G1 continuity across the various surface patches is preserved during the deformation process. Therefore, the C0 and G1 continuities across trimmed surfaces boundaries can be correctly approximated by parametric constraints.
The surface deformation process uses an analogy between the mechanical equilibrium of a rigid bar network and the control polyhedron of free-form surfaces. The bar network parameters may be set up to achieve either isotropic or anisotropic surface deformations. The surface deformation may be located into an arbitrary shaped area to produce either a local or a global deformation.
Parametric modelling of trimmed free-form surfaces is subjected to non-linear geometric constraints. This problem resolution uses an optimization process which minimizes the shape changes of the surface area subjected to the parameters of the deformation process.
An example illustrates the behavior of the parametric modelling process applied to two trimmed surfaces under various sets of continuity and boundary conditions.
Features: Information Carriers for the Product Creation Process
Authors: Vajna Sándor , Wegner Britta 
Published: February 2021

Abstract
Computer-internal product description is limited to models consisting only of the geometry of a technical product and its components. The CAD modellers set up the geometry from elementary elements, which have no direct relation to their meaning for the real product and its production. Logical connections between geometry and important non-geometrical informations are missing. Many informations about the product are not stored and get lost when being modeled with present systems. Therefore CAD systems must provide more comprehensive functionalities than only possibility to describe the geometry of component parts and structural components.
One approach of a uniform representation of different product information is the introduction of features as information carriers, which allow a grouping of data belonging together not only by geometric relation. Features must be implemented in CAx systems for a most complete possible support of the design activities. Feature modelling does not replace known techniques, but improves and completes them.
Dynamic Modelling of a Three Degree-of-Freedom Planar Platform-Type Manipulator
Authors: Attia Hazem A. , Mohamed Maher G. 
Published: February 2021

Abstract
In this paper, the dynamic modelling of a planar three degree-of-freedom platform-type manipulator is presented. A kinematic analysis is carried out initially to evaluate the initial coordinates and velocities. The dynamic model of the manipulator is formulated using a two-step transformation. Initially, the dynamic formulation is written in terms of the Cartesian coordinates of a dynamically equivalent system of particles. Since there is no rotational motion associated with a particle, then the differential equations of motion are derived by applying Newton’s second law to study the translational motion of the particles. The constraint forces between the particles are expressed in terms of Lagrange multipliers. Then, the differential equations of motion are written in terms of the relative joint variables. This leads to an efficient solution and integration of the equations of motion. A numerical example is presented and a computer program is developed.
Power Loss Analysis and the Selection of a Most Efficient Clutching Sequence Associated With an Automatic Transmission Mechanism
Authors: Hsieh Hsin-I , Tsai Lung-Wen 
Published: February 2021

Abstract
This paper presents a methodology for the identification of a most promising clutching sequence associated with an epicyclic-type automatic transmission mechanism. First, a methodology for the analysis of torque distribution on the links of an epicyclic gear mechanism is described. Then, the power loss relations associated with various clutching sequences of an epicyclic gear mechanism are derived. Finally, a procedure for the selection of a most efficient clutching sequence associated with a transmission mechanism is developed.
Use of Penalty Function in Topological Synthesis and Optimization of Strain Energy Density of Compliant Mechanisms
Authors: Frecker Mary I. , Kota Sridhar , Kikuchi Noboru 
Published: February 2021

Abstract
A penalty function approach is used in conjunction with a multi-criteria optimization method for topology synthesis of compliant mechanisms. This method can help facilitate convergence to physically meaningful solutions for problems with a large number of design variables. The second part of the paper is an investigation of the element strain energy density of the optimal solution, where a second stage size optimization routine is developed. The solution from the topology optimization is used as a starting point for the resizing algorithm, which uses an optimality criteria method based on the overall average strain energy density. This second stage optimization more uniformly distributes the element strain energy densities in order to avoid localized areas of high stress or strain.
Automated Shape Optimization Using Parametric Solid Models and p-Adaptive Finite Element Analysis
Authors: Salagame Raviprakash R. 
Published: February 2021

Abstract
A shape optimization capability which is fully integrated with geometry data is developed in this paper. A key feature of the system is the direct use of parametric solid model as the primary design model for shape optimization. This choice leads to a tight coupling between optimization and geometry, a highly desirable feature for an automated design environment. The approach exploits the parametric engine of the solid modeler to update the geometry at the end of each iteration. Responses are generated using polyFEM, a p-adaptive solver supported by a fully automatic three dimensional p-element mesh generator. It is illustrated that the use of p-adaptive technology and parametrized solid model assist us in achieving a high degree of automation.