Movable type | EPFL Graph Search

Movable type (US English; moveable type in British English) is the system and technology of printing and typography that uses movable components to reproduce the elements of a document (usually individual alphanumeric characters or punctuation marks) usually on the medium of paper. Overview The world's first movable type printing technology for paper books was made of porcelain materials and was invented around AD 1040 in China during the Northern Song dynasty by the inventor Bi Sheng (990–1051). The earliest printed paper money with movable metal type to print the identifying code of the money was made in 1161 during the Song dynasty. In 1193, a book in the Song dynasty documented how to use the copper movable type. The oldest extant book printed with movable metal type, Jikji, was printed in Korea in 1377 during the Goryeo dynasty. The spread of both movable-type systems was, to some degree, limited to primarily East Asia. The development of the printing press in Euro

Size segregating intruders in oscillating shear cells.

Christophe Ancey, Tomás Alfredo Trewhela Palacios

Granular avalanches are prone to segregate their particles by their sizes, as a result of shearinduced dilatation. This mechanical response of the granular media facilitates small particle percolation through gaps (kinetic sieving), after which large particles are squeezed upwards by surrounding small particles (squeeze expulsion). The development of simple continuum models for particle-size segregation has provided a better understanding, nevertheless determining the functional dependance of the segregation rates remains as a challenge [1]. In this work we improve the comprehension of the segregation rates, by running simple shear experiments of bidisperse granular materials. The experimental shear cells consists of two parallel plates that rotate over pivot points to generate an oscillatory shear flow within the granular media. Shear cell configuration has been used extensively to study granular segregation [2, 3]. For the present work, two different shear cells have been used: a 2D and a 3D cell. The 2D cell width ranges from 55 to 280 mm, in 15 mm steps. The cell is filled with Polyoxymethylene (POM) disks of different diameters but of the same thickness as the cell gap (around 5 mm). The 3D shear cell consists in two parallel plates that pivot in an upper point located at 80 mm from the movable bottom of the load cell. The separation between the plates is set to 45 mm while the plate thickness is 68 mm. For the 3D shear cell, we used the refractive index match (RIM) technique for visualizing the intruder. Poly(methyl methacrylate) (PMMA) spheres, transparent for the substrate and opaque for the intruders, are used in the experiments along with Triton X-100 to achieve the refractive index matched mixture. We ran experiments using single particle intruders immersed in a differently sized medium in both shear cells. Trajectories and local velocities are measured. An estimation of the segregation rates as a function of the size ratio is also obtained for both cells. Size segregation in the 2D shear cell is only observed for large intruders because of the constraints imposed by the planar configuration. In contrast, in the 3D shear cell small particle percolation occurs and it may stop at middle positions in specific cases, while large intruders didn’t segregate under certain conditions. These observations raise the question: what is initiating and restraining segregation? Within the presented framework, we suggest the interstitial fluid and size ratio may prevent and restrain segregation.

2018

Size segregation fluxes in oscillating shear cells.

Christophe Ancey, Tomás Alfredo Trewhela Palacios

Gravity-driven granular free-surface flows (or granular avalanches) provide ideal conditions for particles to separate based on their size. This size segregation process is caused by shear-induced dilatation that allows the percolation of small particles under gravity (kinetic sieving), after which large particles are pushed upwards by surrounding small particles (squeeze expulsion). Consider able progress has been made in developing simple continuum models for the segregation process, however, the functional dependence of the segregation rates is still relatively poorly understood. The objective of the present work is to gain an understanding of the segregation rates, by using simple shear experiments. Simple shear cells have been widely used to study granular segregation and consist of two tilted parallel plates that rotate about pivot points to create an oscillatory shear within the bulk material. For this work, two different shear cells have been used: a 2D and a 3D cell. The 2D cell width ranges from 55 to 280 mm, in 15 mm steps. The cell is filled with Polyoxymethylene (POM) disks of different diameters but of the same thickness as the cell gap (∼ 5 mm). The 3D shear cell consists in two parallel plates that pivot in an upper point located at 80 mm from the movable bottom of the load cell. The separation between the plates is set to 45 mm while the plate thickness is 68 mm. For the 3D shear cell, we used the refractive index match (RIM) technique for visualizing the intruder. Poly methyl methacrylate (PMMA) spheres, transparent for the substrate and opaque for the intruders, are used in the experiments along with Triton X-100 to achieve the refractive index matched mixture. We ran experiments using single intruders immersed in a differently sized medium in both shear cells. Quantification of the intruders and bulk local velocities is provided. An estimation of the segregation rates as a function of the size ratio is also obtained. Size segregation in the 2D shear cell is only observed for large intruders because of the constraints imposed by the planar configuration. In contrast, in the 3D shear cell small particle percolation occurs and it may stop at middle positions in specific cases. Under certain conditions, large intruders didn’t segregate. These observations raised the question: what is initiating and restraining segregation? Within our experimental framework, we suggest the interstitial fluid and size ratio may prevent and restrain segregation.

2018

Double gate movable body Micro-Electro-Mechanical FET as hysteretic switch: Application to data transmission systems

Daniel Grogg, Mihai Adrian Ionescu, Maher Kayal, Cédric Meinen, Hüseyin Cumhur Tekin, Dimitrios Tsamados

This paper reports on the fabrication, experimental characterization and data transmission application of a double-gate movable body FET. As its name suggests, the proposed movable-body Micro-Electro-Mechanical FET (MB-MEMFET) is a hybrid MEMS-semiconductor device that, in contrast with previously reported Suspended-Gate MOSFET, has a movable body separated by nano-size air gaps from two lateral fixed gates. We report here on the unique abrupt hysteretic characteristic of MB-MEMFET, which for our design offer reproducibility after intense cycling and, due to double gate architecture, a multi-level tunable hysteresis. Based on the

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hysteretic behavior of the new hybrid device we report for the first time a FSK circuit exploiting oscillation at two selectable frequencies (26 kHz and 14 kHz) used to transmit numerical data, which demonstrates the potential of the MB-MEMFET for applications in data transmission systems.

2008

Size segregation fluxes in oscillating shear cells.

Christophe Ancey, Tomás Alfredo Trewhela Palacios

2018

Size segregating intruders in oscillating shear cells.

Christophe Ancey, Tomás Alfredo Trewhela Palacios

2018

Double gate movable body Micro-Electro-Mechanical FET as hysteretic switch: Application to data transmission systems

Daniel Grogg, Mihai Adrian Ionescu, Maher Kayal, Cédric Meinen, Hüseyin Cumhur Tekin, Dimitrios Tsamados

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2008