Search results for "Forming."

Experimental validation of optimisation strategies in hydroforming of T-shaped tubes

2008

For three dimensional tube hydroforming operations (i.e. T or Y shaped tubes) the calibration of both material feeding history and internal pressure path during the process is crucial and many approaches to such optimization were presented; the authors developed some procedures to optimize pressure paths and punch velocity histories with the application of an integrated method FEM - Gradient based optimization tools. In this paper, an experimental validation campaign of the utilized optimization strategies is presented with the aim to assess the effectiveness of the developed procedures. An optimization procedure (gradient based techniques) was applied on the process parameters leading to t…

Non-Canonical WNT Signaling Regulates TGF-²1-Induced Extracellular Matrix Production By Airway Smooth Muscle Cells

2012

Extracorporeal Shock Waves Increase Markers of Cellular Proliferation in Bronchial Epithelium and in Primary Bronchial Fibroblasts of COPD Patients

2020

Chronic obstructive pulmonary disease (COPD) is due to structural changes and narrowing of small airways and parenchymal destruction (loss of the alveolar attachment as a result of pulmonary emphysema), which all lead to airflow limitation. Extracorporeal shock waves (ESW) increase cell proliferation and differentiation of connective tissue fibroblasts. To date no studies are available on ESW treatment of human bronchial fibroblasts and epithelial cells from COPD and control subjects. We obtained primary bronchial fibroblasts from bronchial biopsies of 3 patients with mild/moderate COPD and 3 control smokers with normal lung function. 16HBE cells were also studied. Cells were treated with a…

Multi-directional vs. mono-directional multi-step strategies for single point incremental forming of non-axisymmetric components

2020

Abstract Multi Stage approach is used in Single Point Incremental Forming (SPIF) to overcome one of the main forming limitations, namely the maximum wall angle, characterizing the single stage process. In this paper, different multi-path strategies for the production of parts with flat edges are considered in order to evaluate the best solution in terms of feasibility and geometrical accuracy of the final part: A) mono-directional incremental draw angle; B) mono-directional incremental draw angle with increasing part side; C) Multi-directional approach with non-horizontal path planes. Strain evaluation by means of CGA (Circular Grid Analysis) and defect analysis have been carried out in ord…

Enhancing formability of aluminium alloys by superimposing hydrostatic pressure

2003

Publisher Summary One of the strategic topics in manufacturing engineering is represented by the reduction of components weight. This aim is pursued by utilizing accurate and effective design tools and using lightweight metals such as aluminum, magnesium, and titanium alloys. Unfortunately, such materials often show a poor ductility, and thus enhancing formability is nowadays one of the most relevant research focus, as well as the development of effective and reliable predictive models of defects insurgence during forming processes. In this scenario, forming by means of superimposed hydrostatic pressure represents a promising alternative manufacturing technique. The chapter discusses the si…

Finite element simulation of friction stir welding

2010

Can sad music really make you sad? Indirect measures of affective states induced by music and autobiographical memories

2012

The present study addressed music’s disputed ability to induce genuine sadness in listeners by investigating whether listening to sad music can induce sadness-related effects on memory and judgment. Related aims were to explore how the different mechanisms of music-induced emotions are involved in sadness induced by familiar, self-selected music and unfamiliar, experimenter-selected music, and whether the susceptibility to music-induced sadness is associated with trait empathy. One hundred twenty participants were randomly assigned into four conditions with different tasks: listening to unfamiliar sad or neutral music, or to self-selected sad music, or recalling a sad autobiographical event…

Theoretical and Experimental Studies on the Influence of Process Parameters on Strains and Forces of Single Point Incremental Forming

2014

These paper aims to determine the influence of the most important geometrical parameters (vertical step and punch diameter) on the main strains, thickness reduction and the forces along two directions during the single point incremental forming process (SPIF). The paper comprises a comparative numericalexperimental study, for a simple geometry part obtained by incremental forming. In fact, in the first stage, the punch has a vertical motion with the value of one vertical step. In the second stage, the punch follows a linear trajectory along one side of the die. After each linear trajectory the punch has successive vertical motions, taking one vertical step at a time until the entire geometr…

Design Of Experiments for the optimization the process parameters of thixotropic aluminum alloy

2006

The success of the thixoforming process depends on the possibility to confer to material, when it is found in the semisolid state, a microstructure characterized by globular particles of solid phase surrounded by a continuous film of liquid phase; such microstructure is obtainable through particular thermo-mechanical treatments. In the present research, in order to optimize the influence of process parameters in the step in which the thixotropic properties are conferred to the AA7075 aluminum alloy, the statistic technique of the Design Of Experiments (DOE) has been used. The advantages in the application of such technique are expressible in terms of reduction the times of development of pr…

MicroRNAs Associated With Biological Pathways of Left- and Right-sided Colorectal Cancer.

2020

BACKGROUND/AIM MicroRNAs (miRNAs) regulate the development of colorectal cancer (CRC). We aimed to investigate miRNAs and their relation to cancer-related signaling pathways in site-specific CRC. MATERIALS AND METHODS We used a total of 24 left- and right-sided Finnish CRC samples (discovery cohort) and The Cancer Genome Atlas public mature miRSeq dataset of 201 CRC samples (validation cohort). MiRNA differential expression and biological pathway analyses were performed using DESeq2 and the DIANA/mirPath tool, respectively. RESULTS We found 17 significantly differentially up-regulated [false discovery rate (FDR) <0.05] miRNAs in left-sided CRC ("left miRNAs"), and 15 in right-sided CRC ("ri…