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Influence of Microstructure on Chip Formation when Broaching Ferritic-Pearlitic Steels
Get PDFBroaching is a specific process characterized by relatively low cutting speeds and uncut chip thicknesses. The latter is in the range of 0.1 to 0.25 mm in the roughing section of the tool but can decrease down to 0.0015 mm in the finishing one. This induces drastically different cutting behaviours compared to macroscale processes such as turning. The question of the scale effects in such conditions is thus clearly raising and especially the size and distribution of the microstructure. This paper proposes an investigation to assess the importance of the material heterogeneities on chip formation when broaching ferritic-pearlitic steels
Evaluation of 5G Modulation Candidates WCP-COQAM, GFDM-OQAM, and FBMC-OQAM in Low-Band Highly Dispersive Wireless Channels
Get PDFWe analyse some of the candidates for modulations for 5G: FBMC-OQAM, GFDM-OQAM, and WCP-COQAM. Unlike most of the related bibliographies, which are oriented to mobile communications, our research is focused on 5G in cognitive radio based industrial wireless communications. According to the ultrareliability and low-latency requirements of industrial communications, we simulate the aforementioned modulations in low-band transmissions (carrier frequencies below 6GHz and a bandwidth narrower than 100MHz) through large indoor spaces and severe multipath channels that emulate industrial halls. Moreover, we give detailed information aboutWCP-COQAMand how the windowing affects the protection againstmultipath effect and reduces spectral efficiency compared to GFDM-OQAM.We also compare the aforementioned filtered multicarrier techniques and OFDM in terms of robustness against multipath channels, power spectral density, and spectral efficiency. Based on these results, we aim at providing an approximate idea about the suitability of 5G MCM candidates for industrial wireless communications based on CR
Hole expansion test of third generation steels
Get PDFThe trend towards the implementation of new materials in the chassis of the automobiles is considerably making more complex the manufacturing of the components that built it up. In this scenario materials with higher strengths and lower formabilities are daily faced by tool makers and component producers what reduces the process windows and makes the forming processes to be in the limits of the materials. One of the concerns that tool makers must face during the definition of the tools is the expansion ratios that the holes in the sheet may reach before producing a breakage due to the stretching of the material (also known as edge cracks). For the characterization of such limits, a standard test, the hole expansion test, can be applied so that the limits of the material are known. At the present study, hole expansion tests of a third generation steel, Fortiform1050 with a thickness of 1.2 millimeters have been carried out and compared them to a mild steel, DX54D with a thickness of 0.6 millimeters. A comparison for each material in terms of technology used to punch the hole, mechanical punching vs laser cutting has also been conducted. In addition, the measurement technique (online measurement vs offline measurement) followed in the Hole Expansion Ratio (HER) identification has also been analyzed. Finally, differences between both materials and techniques are presented
New user centered methodologies for software development in the industry 4.0 era
No full textLa cuarta revolución industrial o más conocida como la industria 4.0 ha supuesto una gran transformación en el ámbito de la máquina herramienta. Mediante los sistemas ciber-físicos se logra conectar todos los objetos de la empresa a una red que recoge datos, los almacena y los estudia para ofrecer nuevas soluciones que aumentan la productividad y explotan al máximo el potencial de esta nueva industria inteligente(Lee, 2014). Como consecuencia, los entornos digitales han aumentado de forma considerable, donde la participación de los usuarios es fundamental. Por lo tanto, la comunicación entre la máquina y el usuario es clave para que puedan emplear sus habilidades al máximo y así habilitar la innovación en los servicios y procesos productivos. (Gorecky, 2014)
A Configurable Validation Environment for Refactored Embedded Software : an Application to the Vertical Transport Domain
Get PDFAs systems evolve, their embedded software needs constantly to be refactored. Moreover, given the different needs of different customers, embedded systems require to be customizable. The variability of these systems is large, and requires automated testing solutions. In this paper we propose a methodology that automatically generates validation environments for highly configurable embedded software that is being refactored. The method has allowed for systematically testing a real-world industrial case study involving the software in charge of controlling the doors of an elevator. Finally, we extract the lessons learned from its application
A study of the personalization of spam content using Facebook public information
Get PDFMillions of users per day are affected by unsolicited email campaigns. Spam filters are capable of detecting and avoiding an increasing number of messages, but researchers have quantified a response rate of a 0.006% [1], still significant to turn a considerable profit sending millions of emails, as the spammers do. While research directions are addressing topics such as better spam filters, or spam detection inside online social networks, in this paper we demonstrate that a classic spam model using online social network information can harvest a 7.62% of click-through rate. We collect email addresses from the Internet, complete email owner information using their public social network profile data, and analyze response of personalized spam sent to users according to their profile using a fake website. Finally we demonstrate the effectiveness of these profile-based emails to circumvent spam detection and we compare results between typical spam and personalized spam
Numerical simulation of the roll levelling of third generation fortiform 1050 steel using a nonlinear combined hardening material model
Get PDFElasto–plastic behavior of the third generation Fortiform 1050 steel has been analysed using cyclic tension–compression tests. At the same time, the pseudo elastic modulus evolution with plastic strain was analysed using cyclic loading and unloading tests. From the experiments, it was found that the cyclic behavior of the steel is strongly kinematic and elastic modulus decrease with plastic strain is relevant for numerical modelling. In order to numerically analyse a U-Drawing process, strip drawing tests have been carried out at different contact pressures and Filzek model has been used to fit the experimental data and implement a pressure dependent friction law in Autoform software. Finally, numerical predictions of springback have been compared with the experimentally ones obtained using a sensorized UDrawing tooling. Different material and contact models have been examined and most influencing parameters have been identified to model the forming of these new steels
Análisis Numérico del Efecto de la Termoforesis para la Separación de Diferentes Poblaciones de Exosomas
Get PDFLos sistemas microfluídicos han demostrado ser una alternativa prometedora ante procesos convencionales de separación y caracterización. Este trabajo muestra el estudio numérico del fenómeno de la termoforesis en un microdispositivo para la separación de diferentes poblaciones de exosomas (vesículas entre 40-250nm liberadas por la mayoría de las células) en base a su tamaño. Empleando el software ANSYS Fluent v.16.0 se han analizado diferentes modelos geométricos del microdispositivo, gradientes de temperatura entre la pared superior e inferior y flujos de entrada, con el fin de determinar la trayectoria de los exosomas a través del dispositivo microfluídico y extraer las diferentes poblaciones. En base a los resultados obtenidos se muestra el dispositivo propuesto para la fabricación de un dispositivo eficiente
The Way Cyber Physical Systems Will Revolutionise Maintenance
Get PDFThe way maintenance is carried out is altering rapidly. The introduction of Cyber Physical Systems (CPS) and cloud technologies are providing new technological possibilities that change dramatically the way it is possible to follow production machinery and the necessity to carry out maintenance. In the near future, the number of machines that can be followed from remoteness will explode. At the same time, it will be conceivable to carry out local diagnosis and prognosis that support the adaptation of Condition Based Maintenance (CBM) i.e. financial optimisation can drive the decision whether a machine needs maintenance or not. Further to this, the cloud technology allows to accumulate relevant data from numerous sources that can be used for further improvement of the maintenance practices. The paper goes through the new technologies that have been mentioned above and how they can be benefitted from in practise
Emakumearen mututasun soziala: feminitatearen eta maskulinitatearen estereotipoak
Get PDFMost of the main gender stereotypes that nowadays are still alive can already be discovered in Ancient Greece society. In this paper we will analyze Greek symbolic though using genderperspective. We want to unveil the social roles and the ideal characteristics associated to women and men, in order to understand how sex- difference was built by Greek society during that period.Gaur egun oraindik bizirik dauden rol sozialak eta genero estereotipo nagusiak orduko Antzinako Grezian aurki zitezkeen. Komunikazio honetan Greziar pentsamendu sinbolikoa genero ikuspuntutik analizatuko dugu. Bai emakumezkoen bai gizonezkoen erantzukizun sozialak eta genero ezaugarri idealak argitu nahi ditugu, garai horretan greziar gizartean sexu-diferentzia nola eraiki zen hobeto ulertzeko helburuarekin