Finding the Shape of a Flexible Blade for Free-Form Layered Manufacturing of Plastic Foam Objects

1998 ◽  
Author(s):  
Imre Horváth ◽  
Joris S. M. Vergeest ◽  
Imre Juhász
Keyword(s):  
Order Approximation ◽  
Geometric Model ◽  
Cost Effective ◽  
Soft Materials ◽  
Layered Manufacturing ◽  
Physical Models ◽  
Free Form ◽  
Plastic Foams ◽  
Physically Based ◽  
Definition Of

Abstract The need for rapid, cost-effective and finish-less manufacturing of large sized, sculptured, physical models from various soft materials is increasing in several fields. For objects fabricated from plastic foams an advantageous approach is free-form, thick-layered manufacturing. Although it is technologically demanding, to achieve the best results (a) computer definition of the geometry has to be accurate, (b) the geometric model has to be directly sliced, (c) higher order approximation of the nominal shape is necessary, and (d) a quasi-free-form working out of the front surfaces of the layers is needed. The authors have developed the mathematical and/or technological fundamentals and process of free-form cutting based on heated flexible blades. The shape and the relative positions of the flexible blade are controlled continually as needed by the normal curvatures of the front faces of the layers. The paper elaborates on the computation methods for physically-based and geometrically-based modeling of flexible blades. The algorithms for approximating curve generation and curve matching are also presented. The paper extends to some of the most important aspects of the global thick-layered fabrication process.

An Intelligent Optimization Approach of Feedrate Scheduling Based on Hybrid Simulation Models

2008 ◽  
Vol 392-394 ◽  
pp. 211-215
Author(s):  
Li Qiang Zhang ◽  
Yu Han Wang ◽  
Ming Chen
Keyword(s):  
Tool Path ◽  
Mechanistic Model ◽  
Geometric Model ◽  
Physical Models ◽  
Free Form ◽  
Optimization Approach ◽  
Machining Processes ◽  
Surface Machining ◽  
Feedrate Scheduling ◽  
Free Form Surface

In free-form surface machining, it is essential to optimize the feedrate in order to improve the machining efficiency. Conservative constant feedrate values have been mostly used since there was a lack of physical models and optimization tools for the machining processes. The overall goal of this research is the integration of geometric and mechanistic milling models for force prediction and feedrate scheduling for free-form surface machining. For each tool move a geometric model calculates the cutting geometry parameters, then a mechanistic model uses this information with the constraint force to calculate desired feedrates. The feedrate is written into the part program. When the integrated modeling approach was used, it was shown that the machining time can be decreased significantly along the tool path. Production time in machining propeller example was reduced to 35% compared to constant feedrate cases.

SIMILE: An integrated monitoring system to understand, protect and manage sub-alpine lakes and their ecosystem

2021 ◽  
Author(s):  
Massimiliano Cannata ◽  
Daniele Strigaro ◽  
Fabio Lepori ◽  
Camilla Capelli ◽  
Mauro Veronesi ◽  
...  
Keyword(s):  
Information System ◽  
Remote Sensing Data ◽  
Cost Effective ◽  
Point Of View ◽  
Physical Models ◽  
Anthropogenic Pressure ◽  
Integrated Monitoring ◽  
Lake Lugano ◽  
Critical Issues ◽  
Definition Of

<p>Lakes are a fundamental resource for the Insubric region (cross-border area that includes Ticino, North Lombardy and west Piedmont regions). Therefore the quality of their waters must be protected from the risks caused by the increased anthropogenic pressure and climate change. The main objective of the interreg project named SIMILE (https://interreg-italiasvizzera.eu/database_progetti/simile/) is to support decision making in the definition of management policies through an advanced information system based on data obtained from innovative monitoring systems (automatic, diversified, cost-effective and with high spatial and temporal resolution). The information system will also facilitate the identification of possible critical issues understanding the specific causes in a timely manner by using a common methodology across Switzerland and Italy: specifically for Lake Lugano, Lake Maggiore and Lake Como. The project aims at capitalizing and sharing the experiences of the project partners in the field of monitoring and management of water resources in the project area, in particular in the context of the CIPAIS programs (IT-CH international water protection commission). The information system, fully open, is designed to offer an effective, lowcost and sustainable solution that can be maintained by the project partners beyond the end of the project. From a scientific and technical point of view the project is based on the combination of advanced automatic and continuous observation systems, high resolution remote sensing data processing, citizen science and ecological and physical models. In this presentation we will discuss experiences gained from the deployment of cost-effective monitoring platform and open technologies used for data colection, archive, processing and dissemination.</p><p><img src="https://contentmanager.copernicus.org/fileStorageProxy.php?f=gepj.c525250b070069034701161/sdaolpUECMynit/12UGE&app=m&a=0&c=d3c1099d7d8e917b1c0312e6a43308ab&ct=x&pn=gepj.elif&d=1" alt=""></p>

The Use of Photogrammetry in Piping Design

1983 ◽  
Vol 197 (2) ◽  
pp. 125-138 ◽  
Author(s):  
P A Bracewell ◽  
U R Klement
Keyword(s):  
Information Retrieval ◽  
Mathematical Formulation ◽  
Three Dimensional ◽  
Cost Effective ◽  
Process Industry ◽  
Process Plant ◽  
Definition Of ◽  
High Degree ◽  
Positional Data

Piping design for ‘revamp’ projects in the process industry requires the retrieval of large amounts of ‘as-built’ data from existing process plant installations. Positional data with a high degree of accuracy are required. Photogrammetry, the science of measurement from photographs, was identified in Imperial Chemical Industries plc (ICI) as a suitable tool for information retrieval. The mathematical formulation enabling the definition of three-dimensional positions from photographic information is described. The process of using ICI's photogrammetric system for the definition of complete objects such as structures and pipes is illustrated. The need for specialized photogrammetric software for design purposes is explained. A case study describing how the photogrammetric system has been applied is described and graphical outputs from this exercise are shown. It is concluded that this particular photogrammetric system has proved to be a cost effective and accurate tool for the retrieval of ‘as-built’ information.

scholarly journals Chirping for Large-Scale Maritime Archaeological Survey: A Strategy Developed from a Practical Experience-Based Approach

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Ole Grøn ◽  
Lars Ole Boldreel
Keyword(s):  
Large Scale ◽  
Cost Effective ◽  
Practical Experience ◽  
Archaeological Sites ◽  
Archaeological Survey ◽  
Sea Floor ◽  
Mapping Strategy ◽  
Line Spacing ◽  
Definition Of ◽  
Subbottom Profiling

Archaeological wrecks exposed on the sea floor are mapped using side-scan and multibeam techniques, whereas the detection of submerged archaeological sites, such as Stone Age settlements, and wrecks, partially or wholly embedded in sea-floor sediments, requires the application of high-resolution subbottom profilers. This paper presents a strategy for cost-effective, large-scale mapping of previously undetected sediment-embedded sites and wrecks based on subbottom profiling with chirp systems. The mapping strategy described includes (a) definition of line spacing depending on the target; (b) interactive surveying, for example, immediate detailed investigation of potential archaeological anomalies on detection with a denser pattern of subbottom survey lines; (c) onboard interpretation during data acquisition; (d) recognition of nongeological anomalies. Consequently, this strategy differs from those employed in several detailed studies of known wreck sites and from the way in which geologists map the sea floor and the geological column beneath it. The strategy has been developed on the basis of extensive practical experience gained during the use of an off-the-shelf 2D chirp system and, given the present state of this technology, it appears well suited to large-scale maritime archaeological mapping.

scholarly journals Development of calculated and normative framework in the field of maximum runoff of rain and spring flood: problems and possible solutions

2017 ◽  
pp. 164-170
Author(s):  
E.D. Gopchenko ◽  
M.E. Romanchuk ◽  
V.A. Ovcharuk
Keyword(s):  
Geometric Model ◽  
Hydrological Regime ◽  
Regulatory Document ◽  
Spring Flood ◽  
Probability Of Exceedance ◽  
Normative Framework ◽  
Direct Observations ◽  
Design Characteristics ◽  
Definition Of ◽  
Maximum Runoff

The article deals with the problematic issues  related to the definition of the design characteristics of the maximum runoff of rain and spring floods the  rare  probability of exceedance in the case absence of direct observations for hydrological regime of rivers. A brief review of foreign and domestic methods to determine the maximum runoff of the rivers is discussed. A new calculated and normative framework based on the theory of channel isochronous with using geometric model of  slope and streamflow hydrographs are proposed. The formulas proposed  by the authors is recommended for practical use, as a supplement to a new regulatory document, which is being developed in Ukraine.

scholarly journals The Management of Iron Chelation Therapy: Preliminary Data from a National Registry of Thalassaemic Patients

Anemia ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Adriana Ceci ◽  
Laura Mangiarini ◽  
Mariagrazia Felisi ◽  
Franco Bartoloni ◽  
Angela Ciancio ◽  
...  
Keyword(s):  
Preliminary Data ◽  
Age Groups ◽  
Iron Chelation ◽  
Cost Effective ◽  
National Registry ◽  
Therapeutic Interventions ◽  
Current Status ◽  
Mediterranean Countries ◽  
Important Health ◽  
Definition Of

Thalassaemia and other haemoglobinopathies constitute an important health problem in Mediterranean countries, placing a tremendous emotional, psychological, and economic burden on their National Health systems. The development of new chelators in the most recent years had a major impact on the treatment of thalassaemia and on the quality of life of thalassaemic patients. A new initiative was promoted by the Italian Ministry of Health, establishing a Registry for thalassaemic patients to serve as a tool for the development of cost-effective diagnostic and therapeutic approaches and for the definition of guidelines supporting the most appropriate management of the iron-chelating therapy and a correct use of the available iron-chelating agents. This study represents the analysis of the preliminary data collected for the evaluation of current status of the iron chelation practice in the Italian thalassaemic population and describes how therapeutic interventions can widely differ in the different patients' age groups.

Training a Team with Simulated Team Members

2002 ◽  
Vol 46 (25) ◽  
pp. 2026-2029
Author(s):  
Alma Schaafstal ◽  
Raegan M. Hoeft ◽  
Martin van Schaik
Keyword(s):  
Command And Control ◽  
Cost Effective ◽  
Research Approach ◽  
Control Task ◽  
Promising Alternative ◽  
Team Members ◽  
Long Run ◽  
Military Command ◽  
Definition Of ◽  
And Control

The process of training teams increasingly occurs in synthetic environments. However, it is often still modeled after live team training, including the disadvantages of live training, for example, the fact that all teammates must be available. This paper explores overcoming the disadvantages of human teammates in training teams in synthetic environments, while keeping the advantages of learning in a collaborative and cooperative fashion. Simulated teammates are a promising alternative because they are always available, may be modeled after experienced training personnel, and may be more cost effective in the long run. This paper details a research approach towards the definition of requirements for simulated teammates. In our approach, we carry out a set of experiments using confederates as simulated teammates, in a well-controlled simulation of a military command-and-control task The results of a first experiment show slightly better teamwork skills for those teams trained with simulated teammates.

Experimental Investigation of Factors Influential for the Flexible Blade Based Prototyping Process

1999 ◽  
Author(s):  
Bram de Smit ◽  
Johan J. Broek ◽  
Imre Horváth
Keyword(s):  
Order Approximation ◽  
Experimental Tests ◽  
Influential Factors ◽  
Free Form ◽  
Process Characteristics ◽  
Novel Technology ◽  
Large Numbers ◽  
First Results ◽  
Manufacturing Technologies ◽  
Balanced Optimization

Abstract Due to the need for large numbers of layers and size limitations, current layered manufacturing technologies are not suitable for the fabrication of large sized free-form objects. For this purpose a novel technology of thick layered object manufacturing is being developed, based on higher order approximation of the initial geometry, and the application of a flexible curved cutting tool. The method allows us to produce physical prototypes with less or without any finishing. The technology of cutting foams by means of a heated flexible blade in polystyrene foam offers new possibilities. However to achieve the optimum output, optimization of the process parameters is needed. In this paper a closer look is taken into the process characteristics and the influential factors which are decisive for productive cutting. The authors summarize the results of the executed experimental tests. In these experiments the values of the most influential parameters were systematically changed and the effects were carefully investigated. The first results indicate that the cutting technology is practically feasible, but further research is needed in order to achieve a balanced optimization of the technology from all aspects.

Solid Solutions

1993 ◽  
Author(s):  
Greg M. Anderson ◽  
David A. Crerar
Keyword(s):  
Activity Coefficient ◽  
Practical Interest ◽  
Physical Models ◽  
Ideal Solution ◽  
Ideal Behavior ◽  
Real Solutions ◽  
Ideal Solutions ◽  
Molecular Forces ◽  
Definition Of ◽  
Mixed Component

Real solutions of practical interest to Earth scientists do not behave ideally, although some do come fairly close. The problem of course lies in the stringent and unrealistic physical models we have prescribed for ideal solutions. The molecules of a gas do interact with each other, molecular forces within mixed component liquids really are non-uniform, and the different ions substituting for each other in solids are never exactly alike. So why bother defining an ideal solution in the first place if real systems do not behave that way? In fact, the ideal solution is a very useful artifice. It is something simple against which the behaviour of real solutions can be measured and compared. Our most fundamental definition of an ideal solution was With this as our reference, we can define a non-ideal solution as one for which the activity coefficient of each component i differs from unity The activity coefficient is the single quantity that expresses all deviations from non-ideality for each component of a solution. As we shall see, parameters other than the activity coefficient itself are frequently used to describe non-ideal behavior, but these could, if we wished, be related back to (15.1). Note that we say ⋎i, ≠1.0 in general; there are times when ⋎i = 1.0 for specific conditions (one set of T, P, Xi, etc.) even in highly non-ideal systems. This is just coincidental and certainly does not mean that the system is ideal at that particular point—the activity coefficient would have to be unity under all possible conditions for that to be the case.

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