Search results for "Rope"
showing 10 items of 10402 documents
Assessing the influence of fieldshaper material on magnetic pulse welded interface of Al/Cu joints
2019
Abstract Fieldshaper (FS) is a widely used component in magnetic pulse forming and welding to improve the efficiency of the process. It enables to increase the magnetic pressure experienced by the workpieces during forming and welding. Recent developments in this subject focuses to increase the life time of the fieldshaper and to improve the efficiency by introducing shape optimized designs. In this study, we compare the efficiency of four fieldshapers made of Cuprofor, Siclanic, CuBe2 and Steel. The main focus is given to the effect of material properties while the same geometry was considered for those four fieldshapers. The same welding conditions (discharge voltage of 6kV and air gap of…
Microstructural, mechanical and energy demand characterization of alternative WAAM techniques for Al-alloy parts production
2020
Abstract Additive manufacturing (AM) processes are gathering momentum as an alternative to conventional manufacturing processes. A research effort is being made worldwide to identify the most promising AM approaches. Within this category, wire arc additive manufacturing (WAAM) is among the most interesting, especially when large parts must be manufactured. In this paper, two different WAAM deposition techniques suitable for the deposition of Aluminum alloys, Cold Metal Transfer (CMT) and CMT mix drive, are analyzed and compared. With the aim of obtaining a clear picture concerning the two different techniques, microstructural analyses, mechanical property evaluation and electrical energy de…
Clothoid-Based Three-Dimensional Curve for Attitude Planning
2019
Interest in flying robots, also known as unmanned aerial vehicles (UAVs), has grown during last years in both military and civil fields [1, 2]. The same happens to autonomous underwater vehicles (AUVs) [3]. These vehicles, UAVs and AUVs, offer a wide variety of possible applications and challenges, such as control, guidance or navigation [2, 3]. In this sense, heading and attitude control in UAVs is very important [4], particularly relevant in airplanes (fixed-wing flying vehicles), because they are strongly non-linear, coupled, and tend to be underactuated systems with non-holonomic constraints. Hence, designing a good attitude controller is a difficult task [5, 6, 7, 8, 9], where stabilit…
Conceptual Key Competency Model for Smart Factories in Production Processes
2020
Abstract Background and Purpose: The aim of the study is to develop a conceptual key competency model for smart factories in production processes, focused on the automotive industry, as innovation and continuous development in this industry are at the forefront and represent the key to its long-term success. Methodology: For the purpose of the research, we used a semi-structured interview as a method of data collection. Participants were segmented into three homogeneous groups, which are industry experts, university professors and secondary education teachers, and government experts. In order to analyse the qualitative data, we used the method of content analysis. Results: Based on the anal…
Diode laser welding of ABS: Experiments and process modeling
2009
International audience; The laser beam weldability of acrylonitrile/butadiene/styrene (ABS) plates is determined by combining both experimental and theoretical aspects. In modeling the process, an optical model is used to determine how the laser beam is attenuated by the first material and to obtain the laser beam profile at the interface. Using this information as the input data to a thermal model, the evolution of the temperature field within the two components can be estimated. The thermal model is based on the first principles of heat transfer and utilizes the temperature variation laws of material properties. Corroborating the numerical results with the experimental results, some impor…
Fuzzy Modeling for Uncertain Nonlinear Systems Using Fuzzy Equations and Z-Numbers
2018
In this paper, the uncertainty property is represented by Z-number as the coefficients and variables of the fuzzy equation. This modification for the fuzzy equation is suitable for nonlinear system modeling with uncertain parameters. Here, we use fuzzy equations as the models for the uncertain nonlinear systems. The modeling of the uncertain nonlinear systems is to find the coefficients of the fuzzy equation. However, it is very difficult to obtain Z-number coefficients of the fuzzy equations.
Outward Investments and Productivity: Evidence from European Regions
2016
Castellani D. and Pieri F. Outward investments and productivity: evidence from European regions, Regional Studies. Using a novel data set on international investment projects, this paper builds measures of outward foreign direct investments (FDIs) for 262 regions of the European Union. This allows as estimation to be made of regressions of productivity growth over the 2007–11 period as a function of the number of FDIs. The number of outward FDIs in manufacturing activities is negatively associated with productivity growth in the home region, but investments in sales, distribution and marketing are associated with a boost in local productivity. This is driven especially by investments toward…
Does EU cohesion policy work? Theory and evidence
2017
This paper evaluates the effectiveness of European Cohesion Policy in the regions of 12 EU countries in the period 1991–2008, on the basis of a spatial growth model, which allows for the identification of both direct and indirect effects of EU funds on GDP per worker growth. We find that “Objective 1” funds are characterized by strong spatial externalities and a positive and concave effect on the growth of GDP per worker, which reaches a peak at the ratio funds/GDP of approximately 3 percent and becomes non-significant after 4 percent. “Objective 2” and “Cohesion” funds have nonsignificant effects, while all the other funds exert a positive and significant effect, but their size is very lim…
Model Co-creation from a Modeler’s Perspective: Lessons Learned from the Collaboration Between Ethnographers and Modelers
2018
This paper reports on the authors’ ongoing collaboration on model co-creation, a process that involves not only the reconciliation of methodologies (qualitative vs. quantitative), but also of epistemologies (empirical vs empirical/rationalist) and ontologies (observable referent vs. abstracted referent). The co-creation process has taken place over several months, from early 2017, both in person, teleconferencing and via email. The result was an ethnographic model of the refugee situation in Lesbos, Greece. The qualifier “ethnographic” means that the simulation’s purpose was to capture the problem situation described by ethnographers in a manner that resembles their observations, not to ans…
The Impact of Regionalism on Democracy Building: An Examination of the Southern African Development Community (SADC)
2017
Since the early 1990s, the world has witnessed a new wave of regionalism and a mushrooming of regional integration organizations, particularly in the global South. Focusing on Africa, the Southern African Development Community (SADC) ranks among the most promising examples of regionalism on the continent. The SADC explicitly aims at building and advancing democracy in the region and its member states as part of its broader agenda on regional development. From a political science perspective, there is general agreement that regional integration and parallel institution building can be useful measures to promote and strengthen democratic rule, since an appropriate institutional “lock-in” impl…