Development of cutter for printed circuit board using hydraulic principle

Cutter was known since long times ago as something that was use to cut the thing into smaller piece. Starting from the usual rock at the rock age till the high technology cutter which was make from the precious and valuable material like diamond at this modern age, the cutter was develop to make our daily life more easier and easier. This project is proposed to design and fabricate a cutter as benefit to cut the printed circuit board, the board which contains cuprum as a trace to connect the electricity current to the electronic component like resistors and capacitors. The printed circuit board was widely used in modern electronic and electric component like radio and computer because it can minimize the space and reduce the manufacturing cost by assemble all electronic components together. The usual way to cut the printed circuit board is by using hand because the sensitive of it. By develop the cutter it will make the way to cut the printed circuit board is more efficient without give the damage to the board. In this project, the main purpose of study is to develop the cutter to make sure the cutter can achieve it objective. Developments of cutter are starting by choosing the right cutter's material then design and finally fabricate the cutter

Dozens of virtual impactor orbits eliminated by the EURONEAR VIMP DECam data mining project

Massive data mining of image archives observed with large etendue facilities represents a great opportunity for orbital amelioration of poorly known virtual impactor asteroids (VIs). There are more than 1000 VIs known today; most of them have very short observed arcs and many are considered lost as they became extremely faint soon after discovery. We aim to improve the orbits of VIs and eliminate their status by data mining the existing image archives. Within the European Near Earth Asteroids Research (EURONEAR) project, we developed the Virtual Impactor search using Mega-Precovery (VIMP) software endowed with a very effective (fast and accurate) algorithm to predict apparitions of candidate pairs for subsequent guided human search. Considering a simple geometric model, the VIMP algorithm searches for any possible intersection in space and time between the positional uncertainty of any VI and the bounding sky projection of any image archive. We applied VIMP to mine the data of 451914 Blanco/DECam images observed between 12 Sep 2012 and 11 Jul 2019, identifying 212 VIs that possibly fall into 1286 candidate images leading to either precovery or recovery events. Following a careful search of candidate images, we recovered and measured 54 VIs in 183 DECam images. About 4000 impact orbits were eliminated from both lists, 27 VIs were removed from at least one list, while 14 objects were eliminated from both lists. The faintest detections were around V~24.0, while the majority fall between 21<V<23. The minimal orbital intersection distances remains constant for 67% detections, increasing for eight objects and decreasing for 10 objects. Most eliminated VIs had short initial arcs of less than 5 days. Some unexpected photometric discovery has emerged regarding the rotation period of 2018 DB, based on the close inspection of longer trailed VIs and the measurement of their fluxes along the trails.Comment: Accepted for publication in Astronomy & Astrophysics (27 July 2020

Assessment of the equivalent dipole layer source model in the reconstruction of cardiac activation times on the basis of BSPMs produced by an anisotropic model of the heart

Contains fulltext : 191955.pdf (Publisher’s version ) (Open Access

Topological properties of punctual Hilbert schemes of almost-complex fourfolds (I)

In this article, we study topological properties of Voisin's punctual Hilbert schemes of an almost-complex fourfold $X$. In this setting, we compute their Betti numbers and construct Nakajima operators. We also define tautological bundles associated with any complex bundle on $X$, which are shown to be canonical in $K$-theory

Macrocyclic gelators

The field of low molecular weight supramolecular gels, also known as physical gels, has grown rapidly over the last decade. In these gels, small molecules (gelators) self-assemble through non-covalent interactions, usually into a network of fibres, to trap solvent. Many physical gels are responsive to stimuli and often these types of gels can be reversibly converted from gel to sol. These properties make them ideal candidates for investigation into a range of potential applications, including biomedical, smart materials, sensors and catalysts. This review provides an overview of macrocyclic compounds, particularly the calixarenes, that can form supramolecular gels

Hierarchical Self-Assembly of Supramolecular Helical Fibres from Amphiphilic C3-Symmetrical Functional Tris(tetrathiafulvalenes)

The preparation and self-assembly of the enantiomers of a series of C3-symmetric compounds incorporating three tetrathiafulvalene (TTF) residues is reported. The chiral citronellyl and dihydrocitronellyl alkyl chains lead to helical one dimensional stacks in solution. Molecular mechanics and dynamics simulations combined with experimental and theoretical circular dichroism support the observed helicity in solution. These stacks self-assemble to give fibres that have morphologies that depend on the nature of the chiral alkyl group and the medium in which the compounds aggregate. An inversion of macroscopic helical morphology of the citronellyl compound is observed when compared to analogous 2-methylbutyl chains, which is presumably a result of the stereogenic centre being further away from the core of the molecule. This composition still allows both morphologies to be observed, whereas an achiral compound shows no helicity. The morphology of the fibres also depends on the flexibility at the chain ends of the amphiphilic components, as there is not such an apparently persistent helical morphology for the dihydrocitronellyl derivative as for that prepared from citronellyl chains