The objective of this study is to present a numerical modeling of mixed-mode fracture in isotropic functionally graded materials (FGMs), under mechanical and thermal loading conditions. In this paper, a modified displacement extrapolation technique (DET) was proposed to calculate the stress intensity factor (SIFs) for isotropic FGMs. Using the Ansys Parametric Design Language APDL, the continuous variations of the material properties are incorporated by specified parameters at the centroid of each element. Three numerical examples are presented to evaluate the accuracy of SIFs calculated by the proposed method. Comparisons have been made between the SIFs predicted by the DET and the available reference solutions in the current literature. A good agreement is obtained between the results of the DET and the reference solutions.
Aluminum alloy is a very useful material in light manufacturing. Friction stir welding (FSW) is a solid state assembly process that is achievable for this material. This work aims to characterize the quality of the weld joint by an operation of shaping (folding), it aims to study the rate of elastic return in this weld joint after a folding operation. In this context, the elastic return for the folding process has been modeled using experimental tests under optimal welding conditions.
The paper presents the use of Taguchi method to optimize the cutting of stainless steel by Abrasive Water Jet. Shown are the influence of the most important machining parameters, such a traverse speed, abrasive grains size and concentration of abrasive in the jet on the maximum depth of cut. Analysis of variance - ANOVA was used to determine the effect of machining parameters on the cutting depth. Based on the calculated signal/noise ratios for individual parameters of the cutting process, their impact on cutting depth was determined and optimal process conditions were determined in order to reach the maximum depth of cut. The empirical verification of this process was also performed by comparing the depth of cut predicted and achieved in the tests.
The study defines the concept of e-larning and presents the requirements for conducting an effective course to achieve the assumed learning outcomes. As an element of the introduction to the subject, the advantages and disadvantages of e-learning resulting from the experience over the years of organizations that used or continue to use such forms of teaching are presented. The research part presents the results of research carried out in a deliberately selected group of academic teachers and a group of students. The research results presented and discussed include such aspects as: expectations, advantages, disadvantages, fit, convergence of opinions and proposals for improvement of classes conducted in the e-learning mode in the field of Safety and Health at Work. The study is completed by conclusions and proposals of utilitarian solutions in the field of conducting academic education for selected subjects in a fixed time dimension in the form of e-learning.
The approach of this paper was to analyze the technical borders of industrial robots and to provide an overview of current technology, technical constraints and the potential types of future research suggestion concerning robotic machining. These complex automation machines used in manufacturing processes are an emerging chapter of industrial engineering that contribute to automatically performing operation in subtractive manufacturing and sheet metal forming processes. Compared with CNC machines which have shape limitations and have the restricted working area, the industrial robot is a flexible, cost-saving alternative.
Cardiac arrhythmias occur frequently in valvular patients. In valvular patients the role of echocardiography is essential, due to prognostic variations. A common indication of CT coronarography is the evaluation of the coronary arteries, with the highlighting of the light coronary plaques, but also accurately measures the dimensions of the left atrium and the anatomy of the pulmonary veins. In the last years cardiac MRI (magnetic resonance imaging) has been used in the clinic and research media to establish the gold standard measurement for the volumes of heart cavities, their function and tissue structure. All these three methods are essential for the evaluation and treatment of the cardiac patient with important arrhythmia.
The paper is an interdisciplinary medical and engineering approach that aims to optimize the accuracy of the High Tibial Osteotomy surgical intervention. The axial deviations of the human inferior limb are presented in the first part of the paper. Without altering the shape of the bones, these deviations cause the wear of the knee’s articular cartilage by gonarthrosis. One of the most common and effective treatment modalities for eliminating axial deviations is High Tibial Osteotomy. Because the surgical procedure involves 3D spatial bone cutting, the accuracy of the procedure and thus the success of the operation and the recovery of the patient is dependent on the execution of these cuts. Within this paper, a specialized device is proposed that makes it possible to guide the surgical saw and to accurately perform the correction angles. In the last part of the paper, customization possibilities and fabrication of the main elements of the cutting device using Additive Manufacturing processes are presented.
Estimating the number of identical objects is a fundamental recognition task that requires exhaustive human effort. Automating this task in a warehouse would reduce the human load significantly. In this paper, we propose a method to automatically detect the number of objects, requiring only low-tech hardware and low-processing software, in a manner that provides optimal performance for the needed tasks. This method combines the physical weight of objects and simple image processing that do not require complicated operations, such as the detection of objects and their locations or the extraction of object figures. The experimental results demonstrate the increased effectiveness of the proposed method compared to methods based on weight alone or on image processing alone.
The research aims to test polymer materials as the plastic materials: UHMWPE and POM, to observe there characteristics, to determing how they can be used and what we can obtain from them. We wanted to see the strong and the weak values that characterize them, what kind of parts we can produce from them and in what case we can use it. By applying this tests is necessary in order to see real datas that can help you compare them, and lead you to conclusions. Using these methods of testing materials leads to the establishment of real properties of the material and to the establishment of new configurations necessary to be made to the manufactured parts.