scholarly journals 3D-Printed All-Dielectric Electromagnetic Encoders with Synchronous Reading for Measuring Displacements and Velocities

Sensors ◽  
2020 ◽  
Vol 20 (17) ◽  
pp. 4837
Author(s):  
Cristian Herrojo ◽  
Ferran Paredes ◽  
Ferran Martín
Keyword(s):  
Dielectric Material ◽  
Low Cost ◽  
Good Alternative ◽  
The Other ◽  
Clock Signal ◽  
Aging Effects ◽  
Absolute Position ◽  
De Bruijn Sequence ◽  
3D Printed ◽  
The Absolute

In this paper, 3D-printed electromagnetic (or microwave) encoders with synchronous reading based on permittivity contrast, and devoted to the measurement of displacements and velocities, are reported for the first time. The considered encoders are based on two chains of linearly shaped apertures made on a 3D-printed high-permittivity dielectric material. One such aperture chain contains the identification (ID) code, whereas the other chain provides the clock signal. Synchronous reading is necessary in order to determine the absolute position if the velocity between the encoder and the sensitive part of the reader is not constant. Such absolute position can be determined as long as the whole encoder is encoded with the so-called de Bruijn sequence. For encoder reading, a splitter/combiner structure with each branch loaded with a series gap and a slot resonator (each one tuned to a different frequency) is considered. Such a structure is able to detect the presence of the apertures when the encoder is displaced, at short distance, over the slots. Thus, by injecting two harmonic signals, conveniently tuned, at the input port of the splitter/combiner structure, two amplitude modulated (AM) signals are generated by tag motion at the output port of the sensitive part of the reader. One of the AM envelope functions provides the absolute position, whereas the other one provides the clock signal and the velocity of the encoder. These synchronous 3D-printed all-dielectric encoders based on permittivity contrast are a good alternative to microwave encoders based on metallic inclusions in those applications where low cost as well as major robustness against mechanical wearing and aging effects are the main concerns.

scholarly journals Graphite Modified Polylactide (PLA) for 3D Printed (FDM/FFF) Sliding Elements

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1250 ◽  
Author(s):  
Robert E. Przekop ◽  
Maciej Kujawa ◽  
Wojciech Pawlak ◽  
Marta Dobrosielska ◽  
Bogna Sztorch ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fracture Stress ◽  
Low Cost ◽  
Chemical Properties ◽  
Spare Parts ◽  
The Other ◽  
Graphite Content ◽  
Before And After ◽  
3D Printed ◽  
And Chemical Properties

With the development of 3D printing technology, there is a need to produce printable materials with improved properties, e.g., sliding properties. In this paper, the authors present the possibilities of producing composites based on biodegradable PLA with the addition of graphite. The team created composites with the following graphite weight contents: 1%, 2.5%, 5%, 7.5%, and 10%. Neat material was also subjected to testing. Tribological, mechanical, and chemical properties of the mentioned materials were examined. Measurements were also made after keeping the samples in ageing and climatic ovens. Furthermore, SEM observations of samples before and after friction tests were carried out. It was demonstrated that increasing graphite content caused a significant decrease in wear (PLA + 10% graphite had a wear rate three times lower than for a neat material). The addition of graphite did not adversely affect most of the other properties, but it ought to be noted that mechanical properties changed significantly. After conditioning in a climatic oven PLA + 10% graphite has (in comparison with neat material) 11% lower fracture stress, 47% lower impact strength, and 21% higher Young’s modulus. It can be certainly stated that the addition of graphite to PLA is a step towards obtaining a material that is low-cost and suitable for printing sliding spare parts.

VI.—The Zone of Offaster pilula in the South English Chalk

1914 ◽  
Vol 1 (11) ◽  
pp. 509-513 ◽  
Author(s):  
R. M. Brydone
Keyword(s):  
The Other ◽  
The South ◽  
Absolute Position ◽  
Isle Of Wight ◽  
Single Section ◽  
Unfavourable Condition ◽  
The Absolute ◽  
First Time ◽  
Universal Rule ◽  
The Way

I Claim to have now shown that the zone of O. pilula as established in 1912 for Hants and the Salisbury area holds good in its broad features also for Sussex, the Isle of Wight, and Dorset, and that it is almost equally constant in some of its minor features, especially the way in which it ends in a bed 2 ft. 6 in. to 3 feet thick with a flint seam in the middle of it and enclosed by two marl seams. I am only prevented by a single section in Hants from setting this up as the universal rule in all sections I have seen. In The Stratigraphy I assigned pits Nos. 1065, 1066, and 1067, the last of which will be more readily recognized as Mottisfont Whiting Pit, to the zone of A. quadratus, because on examining them for the purposes of that work for the first time since 1892 I had failed to find evidence of more than a seam of O. pilula without any others of the associated fossils of the zone. At the time of that examination all the pits were in a most unfavourable condition. Since then I have been keeping regular watch on the Whiting Pit (No. 1067), and I soon found that the subzone of abundantO. pilula must be represented at its base, and then that the upper belt of O. pilula in that subzone must be exposed: but it was only this spring that I was able to fix the absolute position of the boundary between the zones of O. pilula and A. quadratus in the Whiting Pit, and at the same time, owing to developments in the other two pits, to identify the cinctus belt in the old face and the lower belt of O. pilula in the new workings (and probably also at the lowest point of the old face) of Pit No. 1066, and the lower belt of O. pilula at the base of Pit No. 1065.

The World after the End of the World

2017 ◽  
Vol 39 (2) ◽  
pp. 265-276 ◽  
Author(s):  
Kas Saghafi
Keyword(s):  
The Other ◽  
The World ◽  
History Of ◽  
The Absolute ◽  
End Of The World

In several late texts, Derrida meditated on Paul Celan's poem ‘Grosse, Glühende Wölbung’, in which the departure of the world is announced. Delving into the ‘origin’ and ‘history’ of the ‘conception’ of the world, this paper suggests that, for Derrida, the end of the world is determined by and from death—the death of the other. The death of the other marks, each and every time, the absolute end of the world.

Moderne Ikonen

2009 ◽  
Vol 54 (2) ◽  
pp. 123-143
Author(s):  
Bernadette Collenberg-Plotnikov
Keyword(s):  
Mass Culture ◽  
Visual Experience ◽  
Modern Art ◽  
The Other ◽  
Recent Discussion ◽  
Christian Church ◽  
Other Hand ◽  
The Absolute ◽  
Modern Mass

›Ikonen‹ sind heute nicht mehr nur die Ikonen der christlichen Kirche, sondern vor allem die Ikonen der modernen Massenkultur. Beide Arten von Ikonen werden in der neueren Kunstreflexion aufgegriffen: Kunst gilt entweder, verstanden als Erbin der religiösen Ikone, als Phänomen, das Absolutes in singulärer Weise anschaulich er- fahrbar macht. Oder aber die Kunst gilt umgekehrt lediglich als Klasse in der Welt der säkularen Ikonen. Demgegenüber wird im Beitrag erstens die These vertretenwerden, daß die neuere Kunst sowohl Aspekte transzendenter als auch immanenter Ikonen umfaßt. Zugleich ist es aber, so die zweite These, für unser Kunstverständnis charakteristisch, ein theoretisches Kontrastverhältnis zwischen Kunst und Ikone an- zunehmen. Dieses gründet auf einer spezifischen Reflexivität der Kunst, durch die sie sich von der Ikone beiderlei Art kategorial unterscheidet. Today, the word ›icon‹ usually no longer refers to the icons of the Christian church, but to the icons of the modern mass-culture. Both sorts of icons play a key-role in the recent discussion about art: Either art is supposed to be a descendant of the religious icon, a phenomenon that gives us a singular visual experience of the Absolute. On the other hand, art is supposed to be just one class among others in the wide world of the secular icons. In contrast to these two positions this essay contends that modern art comprehends aspects of transcendent as well as of immanent icons. Furthermore, it argues that at the same time it is characteristic for our notion of art to suppose a contrast between art and icon. This contrast is based on a specific reflectivity of art, which marks a categorical difference between art and both sorts of icons.

SAE 1039

Alloy Digest ◽  
1977 ◽  
Vol 26 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Low Cost ◽  
Manganese Content ◽  
Heat Treating ◽  
General Purpose ◽  
Carbon Steels ◽  
The Other ◽  
Steel Mills ◽  
Medium Strength ◽  
Hot Rolled

Abstract SAF 1039 steel can be used in the hot-rolled, normalized, oil-quenched-and-tempered or water-quenched-and-tempered condition for general-purpose construction and engineering. Its manganese content is a little higher than some of the other standard carbon steels with comparable carbon levels; this gives it slightly higher hardenability and hardness. It provides medium strength and toughness at low cost. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: CS-66. Producer or source: Carbon steel mills.

Pioneering Low-Cost 3D-Printed Transtibial Prosthetics to Serve a Rural Population in Sierra Leone

2020 ◽  
Author(s):  
Merel van der Stelt ◽  
Martin P. Grobusch ◽  
Abdul R. Koroma ◽  
Marco Papenburg ◽  
Ismaila Kebbie ◽  
...  
Keyword(s):  
Sierra Leone ◽  
Rural Population ◽  
Low Cost ◽  
3D Printed

Using Low Temperature, Cost-effective and Green Methods to Carbon Nanohorn Synthesis

2019 ◽  
Vol 9 (2) ◽  
pp. 157-160
Author(s):  
Ali Hasani
Keyword(s):  
Laser Ablation ◽  
Melting Point ◽  
Palm Olein ◽  
Arc Discharge ◽  
Low Cost ◽  
The Other ◽  
High Yield ◽  
Reaction Field ◽  
Carbon Nanohorns ◽  
Graphite Rod

Background: Laser ablation method has high-yield and pure SWCNHs. On the other hand, arc discharge methods have low-cost production of SWCNHs. However, these techniques have more desirable features, they need special expertness to use high power laser or high current discharge that either of them produces very high temperature. As for the researches, the temperatures of these techniques are higher than 4727°C to vaporize the graphite. So, to become aware of the advantages of SWCNHs, it is necessary to find a new way to synthesize SWCNHs at a lower temperature. In other words, reaction field can be expandable at a moderate temperature. This paper reports a new way to synthesize SWCNHs at an extremely reduced temperature. Methods: According to this study, the role of N2 is the protection of the copper holder supporting the graphite rod by increasing heat transfer from the holder. After the current of 70 A was supplied to the system, the temperature of graphite rod was raised to 1600°C. It is obvious that this temperature is somehow higher than the melting point of palladium, 1555°C, and much lower than graphite melting point, 3497°C. Results: Based on the results, there are transitional precursors simultaneous with the SWCNHs. This composition can be created by distortion of the primary SWCNTs at the higher temperature. Subsequently, each SWCNTs have a tendency to be broken into individual horns. With increasing the concentration of the free horns, bud-like SWCNHs can be produced. Moreover, there are individual horns almost separated from the mass of single wall carbon nanohorns. This structure is not common in SWCNHs synthesized by the usual method such as arc discharge or laser ablation. Through these regular techniques, SWCNHs are synthesized as cumulative particles with diameters about 30-150 nm. Conclusion: A simple heating is needed for SWCNTs transformation to SWCNHs with the presence of palladium as catalyst. The well-thought-out mechanism for this transformation is that SWCNTs were initially changed to highly curled shape, and after that were formed into small independent horns. The other rout to synthesize SWCNHs is the pyrolysis of palm olein at 950°C with the assistance of zinc nitrate and ferrocene. Palm olein was used as a promising, bio-renewable and inexpensive carbon source for the production of carbon nanohorns.

scholarly journals UV Inscription and Pressure Induced Long-Period Gratings through 3D Printed Amplitude Masks

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 1977
Author(s):  
Ricardo Oliveira ◽  
Liliana M. Sousa ◽  
Ana M. Rocha ◽  
Rogério Nogueira ◽  
Lúcia Bilro
Keyword(s):  
State Of The Art ◽  
Low Cost ◽  
Resonance Wavelength ◽  
Complex Structures ◽  
Pressing Method ◽  
Long Period ◽  
Long Period Gratings ◽  
3D Printed ◽  
Mechanical Pressing ◽  
First Time

In this work, we demonstrate for the first time the capability to inscribe long-period gratings (LPGs) with UV radiation using simple and low cost amplitude masks fabricated with a consumer grade 3D printer. The spectrum obtained for a grating with 690 µm period and 38 mm length presented good quality, showing sharp resonances (i.e., 3 dB bandwidth < 3 nm), low out-of-band loss (~0.2 dB), and dip losses up to 18 dB. Furthermore, the capability to select the resonance wavelength has been demonstrated using different amplitude mask periods. The customization of the masks makes it possible to fabricate gratings with complex structures. Additionally, the simplicity in 3D printing an amplitude mask solves the problem of the lack of amplitude masks on the market and avoids the use of high resolution motorized stages, as is the case of the point-by-point technique. Finally, the 3D printed masks were also used to induce LPGs using the mechanical pressing method. Due to the better resolution of these masks compared to ones described on the state of the art, we were able to induce gratings with higher quality, such as low out-of-band loss (0.6 dB), reduced spectral ripples, and narrow bandwidths (~3 nm).

scholarly journals BoSL FAL Pump: a small, low-cost, easily constructed, 3D-printed peristaltic pump for sampling of waters

HardwareX ◽  
2021 ◽  
pp. e00214
Author(s):  
David T. McCarthy ◽  
Baiqian Shi ◽  
Miao Wang ◽  
Stephen Catsamas
Keyword(s):  
Low Cost ◽  
Peristaltic Pump ◽  
3D Printed

scholarly journals Antioxidant activity of Lactobacillus plantarum NJAU-01 in an animal model of aging

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Qingfeng Ge ◽  
Bo Yang ◽  
Rui Liu ◽  
Donglei Jiang ◽  
Hai Yu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Antioxidant Capacity ◽  
Lactobacillus Plantarum ◽  
Meat Product ◽  
The Other ◽  
Oxidative Stress Marker ◽  
Control Group ◽  
Intragastric Administration ◽  
Aging Effects ◽  
Sterile Saline

Abstract Background Excessive reactive oxygen species (ROS) can cause serious damage to the human body and may cause various chronic diseases. Studies have found that lactic acid bacteria (LAB) have antioxidant and anti-aging effects, and are important resources for the development of microbial antioxidants. This paper was to explore the potential role of an antioxidant strain, Lactobacillus plantarum NJAU-01 screened from traditional dry-cured meat product Jinhua Ham in regulating D-galactose-induced subacute senescence of mice. A total of 48 specific pathogen free Kun Ming mice (SPF KM mice) were randomly allocated into 6 groups: control group with sterile saline injection, aging group with subcutaneously injection of D-galactose, treatments groups with injection of D-galactose and intragastric administration of 107, 108, and 109 CFU/mL L. plantarum NJAU-01, and positive control group with injection of D-galactose and intragastric administration of 1 mg/mL Vitamin C. Results The results showed that the treatment group of L. plantarum NJAU-01 at 109 CFU/mL showed higher total antioxidant capacity (T-AOC) and the antioxidant enzymatic activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) than those of the other groups in serum, heart and liver. In contrast, the content of the oxidative stress marker malondialdehyde (MDA) showed lower levels than the other groups (P < 0.05). The antioxidant capacity was improved with the supplement of the increasing concentration of L. plantarum NJAU-01. Conclusions Thus, this study demonstrates that L. plantarum NJAU-01 can alleviate oxidative stress by increasing the activities of enzymes involved in oxidation resistance and decreasing level of lipid oxidation in mice.

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