Elliptical torus cutter tool path generation based on minimum distance computation

In mould manufacture the elliptical torus cutters are used for their high cutting velocity, but the special geometry also brings issues in tool path generating and machining quality controlling. In this paper a guide curve tool path generating method for elliptical torus cutters is presented with the cutter location points computed by a minimum distance algorithm and the path spacing determined by an adaptive method. In the minimum distance algorithm, the calculation is resolved into an iterative process from point to freeform surface and an algebraic calculation process from point to elliptical torus surface considering the geometry of the cutter, which reduces the iterative process and improves the computing speed. In the adaptive path spacing method, the contacting geometry between the elliptical cutter and the workpiece surface is analysed and the relations among the scallop height, the tool tilt angle and the path spacing are deduced, based on which the guide curves are adjusted in advance to control the scallop height. Calculating examples and experiments are carried out, showing that the consuming time of cutter location (CL) points computation algorithm is reduced by 30% comparing to earlier method, and the adaptive path spacing method performs better than constant method in both scallop height controlling and tool path shortening. The results indicate that the presented tool path generating method can help to reduce both the machining and machine waiting time as well as ensuring the machining quality.

Intuitionistic Fuzzy (IF) Overlap Functions and IF-Rough Sets with Applications

Overlap function (which has symmetry and continuity) is widely used in image processing, data classification, and multi-attribute decision making problems. In recent years, theoretical research on overlap function has been extended to interval valued overlap function and lattice valued overlap function, but intuitionistic fuzzy overlap function (IF-overlap function) has not been studied. In this paper, the concept of IF-overlap function is proposed for the first time, then the generating method of IF-overlap function is given. The representable IF-overlap function is defined, and the concrete examples of representable and unrepresentable IF-overlap functions are given. Moreover, a new class of intuitionistic fuzzy rough set (IF-roght set) model is proposed by using IF-overlap function and its residual implication, which extends the IF-rough set model based on intuitionistic fuzzy triangular norm, and the basic properties of the new intuitionistic fuzzy upper and lower approximate operators are analyzed and studied. At the same time, the established IF-rough set based on IF-overlap function is applied to MCDM (multi-criteria decision-making) problems, the intuitionistic fuzzy TOPSIS method is improved. Through the comparative analysis of some cases, the new method is proved to be flexible and effective.

Digital Generating Method for Cylindrical Helical Gear based on Indexable Disk Milling Cutter

To solve the problem of low efficiency in digital generating machining for producing small or medium batches of helical gears, a method to improve the machining efficiency with an indexable disc milling cutter is presented in this paper. First, the mathematical model of the tooth profile and the indexable disc milling cutter are established. Second, according to the spatial free-form envelope theory, the overall planning scheme of the tool path is given; the relative position and the relative transformation matrix of the tool and tooth profile during digital generating machining using the indexable disc milling cutter are solved, the simulation cutting and actual cutting experiments are conducted, and the cutting efficiency per unit time and cutting simulation time of the two tools under the same deformation conditions is obtained through a finite element analysis experiment. The results show that the cutting efficiency of the indexable disc milling tool was 2–3 times higher than that of the end mill cutter.

Kidney-lung crosstalk during SARS-CoV-2 infection: In silico hypothesis-generating method for COVID-19 models

BackgroundPublicly available genomics datasets have been growing drastically during the past decades. Although most of these datasets were initially generated to answer a pre-defined scientific question, their re-purposing became useful when new challenges such as COVID-19 arise. While the establishment and use of experimental models of COVID-19 are in progress, the potential hypotheses for mechanisms of onset and progression of COVID-19 can be generated by using in silico analysis of known COVID-19 conditions and SARS-CoV-2 targets. MethodsSelecting condition: COVID-19 infection leads to acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI). There is increasing data demonstrating mechanistic links between AKI and ARDS. Selecting targets: SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) and transmembrane protease, serine 2 (TMPRSS2) for cell entry. We hypothesized that modeling AKI and ARDS would lead to changes in kidney and lung ACE2 and TMPRSS2. We therefore evaluated expression of ACE2 and TMPRSS2 as well as other novel molecular players of AKI and AKI-lung cross-talk in publicly available microarray datasets GSE6730 and GSE60088, which represented gene expression of lungs and kidneys in mouse models that resembled lung-kidney injury seen during SARS-CoV-2 infection.ResultsExpression of COVID-19 related genes ACE2 and TMPRSS2 was downregulated in lungs at early stages of injury. At a later stage, the expression of ACE2 decreased further, while expression of TMPRSS2 recovered. In kidneys, both genes were downregulated by AKI, but not by distant lung injury. We also identified 53 kidney genes upregulated by pneumonia and mechanical ventilation (PMV); and 254 lung genes upregulated by AKI, 9 genes of which were common to both organs. 3 of 9 genes were previously linked to kidney-lung cross-talk: Lcn2 (Fold Change (FC)Lung(L) =18.6, FCKidney(K) =6.32), Socs3 (FCL =10.5, FCK =10.4), Inhbb (FCL =6.20, FCK =6.17). This finding validates the current approach and reveals new 6 candidates, including Maff (FCL =7.21, FCK =5.98).ConclusionsUsing our in-silico approach, we identified changes in COVID-19 related genes ACE2 and TMPRSS2 in traditional mouse models of AKI and lung cross-talk. We also found changes in the new candidate genes, which could be involved in the combined kidney-lung injury during COVID-19

Determining the width of a layer cut with saws with multidirectional teeth

To predict the workability of a tool structure at the design stage, it is necessary to calculate the parameters of the cut layer when this tool is used because the cut layer’s size determines the strength and dynamic characteristics of the cutting process. It is known that the size and shape of the cut layer are affected by the allowance cutting scheme embedded in the tool design. Therefore, the parameters of the cut layer with the tool must be investigated taking into consideration the actual shapes and location of the cutting edges of the tool teeth and the cutting scheme with individual teeth. Existing analytical dependences on determining the thickness of the cut layer do not take into consideration the group arrangement of the teeth, which have a different shape and location of their cutting edges. Therefore, a procedure for determining the thickness of the cut layer analytically has been proposed, using the example of circular saws with multidirectional teeth while taking into consideration the patterns in the arrangement of the cutting edges of individual teeth and the real movements of the tool during its operation. The proposed procedure makes it possible to determine the parameters of the layer cut with the tool at both constant and progressive allowance cutting schemes. One can also specify the parameters of the cut layer at any time of the tool’s operation and analyze the change in the shape of the slice in time. Based on the analysis of the parameters of the cut layer, it has been established that saws with multidirectional teeth do not work with the entire width of the cutting edge but only in its part, whose share does not exceed 55 % of the width of the tool. The procedure reported here could be used to determine the loading of the cutting tool part with a more complex cutting scheme, which also includes tools that are operated by the form-generating method

An Innovative Technique of Electricity Generation and Use of Washing Machine by Treadmill

hence, the basic needs of human life are power, hence the demand of electricity generating method is increasing day by day. It can manipulate development any country of a world. Now, for developing electric power generation we have implemented an innovative idea of generating electricity from the use of the specially designed treadmill with the new specially designed washing machine, which will work when a human being runs over a treadmill for exercise, which is an integral part of modern digital society. India is a developing country because of it has limited resources. In India, most of the energy sources are diminishing day by day. On the other hand, conventional energy resources are responsible for pollution and global warming. That is why we need a non-conventional energy source to develop electric power generating which is eco-friendly, clean and sustainable. Increasing population of the world is also a major factor of increase in energy demand that is why scientists are exploring major and minor energy resources to fulfill energy demands