High-resolution electroluminescent imaging of pressure distribution using a piezoelectric nanowire LED array

2013 ◽  
Vol 7 (9) ◽  
pp. 752-758 ◽  
Author(s):  
Caofeng Pan ◽  
Lin Dong ◽  
Guang Zhu ◽  
Simiao Niu ◽  
Ruomeng Yu ◽  
...  
Keyword(s):  
High Resolution ◽  
Pressure Distribution ◽  
Led Array

scholarly journals A Cost-Effective In Situ Zooplankton Monitoring System Based on Novel Illumination Optimization

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3471
Author(s):  
Zhiqiang Du ◽  
Chunlei Xia ◽  
Longwen Fu ◽  
Nan Zhang ◽  
Bowei Li ◽  
...  
Keyword(s):  
High Resolution ◽  
Imaging System ◽  
Physiological State ◽  
Cost Effective ◽  
In Situ Monitoring ◽  
Measuring System ◽  
Target Area ◽  
Image Processing Algorithm ◽  
Led Array

A cost-effective and low-power-consumption underwater microscopic imaging system was developed to capture high-resolution zooplankton images in real-time. In this work, dark-field imaging was adopted to reduce backscattering and background noise. To produce an accurate illumination, a novel illumination optimization scheme for the light-emitting diode (LED) array was proposed and applied to design a lighting system for the underwater optical imaging of zooplankton. A multiple objective genetic algorithm was utilized to find the best location of the LED array, which resulted in the specific illumination level and most homogeneous irradiance in the target area. The zooplankton imaging system developed with the optimal configuration of LEDs was tested with Daphnia magna under laboratory conditions. The maximal field of view was 16 mm × 13 mm and the optical resolution was 15 μm. The experimental results showed that the imaging system developed could capture high-resolution and high-definition images of Daphnia. Subsequently, Daphnia individuals were accurately segmented and their geometrical characters were measured by using a classical image processing algorithm. This work provides a cost-effective zooplankton measuring system based on an optimization illumination configuration of an LED array, which has a great potential for minimizing the investment and operating costs associated with long-term in situ monitoring of the physiological state and population conditions of zooplankton.

scholarly journals Cheap, Versatile, and Turnkey Fabrication of Microfluidic Master Molds Using Consumer Grade LCD Stereolithography 3D Printing

2021 ◽  
Author(s):  
Vincent G. Colin ◽  
Théo A. Travers ◽  
Denis Gindre ◽  
Régis Barillé ◽  
Matthieu Loumaigne
Keyword(s):  
High Resolution ◽  
3D Printing ◽  
Cost Efficiency ◽  
Soft Lithography ◽  
Microfluidic Devices ◽  
Teaching Tool ◽  
3D Printer ◽  
Uv Led ◽  
Led Array ◽  
3D Printers

Abstract The recent development of 3D printers allowed a lot of limitations in the field of microfabrication to be circumvented. The ever-growing chase for smaller dimensions has come to an end in domains such as microfluidics, and the focus now shifted to a cost-efficiency challenge. In this paper, the use of a high-resolution stereolithography LCD 3D printer is investigated for fast and cheap production of microfluidic master molds. More precisely, we use the UV LED array and the LCD matrix of the printer as an illuminator and a programmable photomask for soft lithography. The achieved resolution of around 100µm is mainly limited by the pixel geometry of the LCD matrix. A tree-shape gradient mixer was fabricated using the presented method. It shows very good performances despite the presence of sidewall ripples due to the uneven pixel geometry of the LCD matrix. Given its sub-€1,000 cost, this method is a very good entry point for labs wishing to explore the potential of microfluidic devices in their experiments, as well as a teaching tool for introducing students to microfluidics.

scholarly journals HARVEST: High-Resolution Haptic Vest and Fingertip Sensing Glove That Transfers Tactile Sensation of Fingers to the Back

2021 ◽  
Vol 11 (3) ◽  
pp. 1298
Author(s):  
Taha Moriyama ◽  
Hiroyuki Kajimoto
Keyword(s):  
High Resolution ◽  
Pressure Distribution ◽  
Tactile Sensation ◽  
Tactile Information ◽  
Tactile Receptors ◽  
Finger Skin

Human fingertips are densely populated with tactile receptors and are hence incredibly sensitive. However, wearing gloves on the fingers drastically reduces the tactile information available to the fingertips, such as the texture and shape of the object, and makes it difficult to perform dexterous work. As a solution, in this study, we developed a high-resolution haptic vest that transfers the tactile sensation of the fingertips to the back. The haptic vest contains 80 voice-coil type vibrators which are located at each of the two discrimination thresholds on the back and can be driven independently. The tactile sensation of the fingertips is transferred to the back using the developed haptic vest in combination with a sensing glove that can detect the pressure distribution on the finger skin at up to 100 points. Different experiments were conducted to validate the performance of the proposed haptic vest and sensing gloves. The use of the haptic vest and the sensing glove enabled the user to perceive the shape of a planar object more accurately when compared to the case where the user wore only the glove.

Method for Calculating Plastic Deformation of High Resolution and Large Contact Area

2021 ◽  
Vol 144 (1) ◽  
Author(s):  
S. Sklenak ◽  
D. Mevissen ◽  
J. Brimmers ◽  
C. Brecher
Keyword(s):  
Plastic Deformation ◽  
High Resolution ◽  
Pressure Distribution ◽  
Rough Surface ◽  
Tribological Properties ◽  
Contact Area ◽  
Three Dimensional ◽  
Rolling Contact ◽  
Contact Algorithm ◽  
Large Contact Area

Abstract In a rolling contact, the tribological properties in terms of friction, wear, and fatigue are significantly influenced by the surface roughness. Due to solid contact of the surfaces in the contact area, the roughness and thus also the tribological properties change during the service life of the contact. The initial load leads to major changes of the tribological properties figured out by Brecher et al. (2019, “Influence of the Metalworking Fluid on the Micropitting Wear of Gears,” Wear, 61(434–435), p. 202996). Prediction of the initial changes in topography in the contact area is necessary for specific optimization of rolling contacts. Especially for dry rolling–sliding contact, the roughness of the surfaces is crucial for the lifetime, which is part of the investigations within the DFG priority program 2074 (357505886). In this work, an elastic-plastic contact algorithm for calculating plastic deformation for dry contact of rough surfaces with large contact area and high resolution is presented. Due to the nonlinearity behavior associated with plastic deformation, the plastic contact algorithm is based on an iterative approach. An optimized meshing strategy is implemented to calculate the elastic pressure distribution on the surface. Corresponding to the two-dimensional pressure distribution, the three-dimensional stress distribution allows the consideration of residual stresses and interactions of the microscopic peaks of the rough surface. Furthermore, the three-dimensional plastic strain distribution allows the application of an analytical approach to represent the plastic deformation of the surface. Finally, the solution of a plastic contact calculation with an exemplary topography measured on a real rough surface is presented.

Method for Calculating Normal Pressure Distribution of High Resolution and Large Contact Area

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
C. Brecher ◽  
D. Renkens ◽  
C. Löpenhaus
Keyword(s):  
High Resolution ◽  
Pressure Distribution ◽  
Surface Topography ◽  
Contact Area ◽  
Normal Pressure ◽  
Rolling Contact ◽  
Sliding Contacts ◽  
Contact Areas ◽  
Irregular Grids ◽  
Disk Rolling

The exact calculation of contact stresses below the surface is the basis for optimizing load capacity of heavily loaded rolling–sliding contacts. The level of stress is significantly influenced by the normal pressure distribution within the contact area, which occurs as a result of the transferred normal force and the contact geometry. In this paper, a new method for high resolution pressure calculation of large contact areas is presented. By this, measured surface topography can be taken into account. The basis of the calculation method is the half-space theory according to Boussinesq/Love. Instead of regular grids, optimized meshing strategies are applied to influence the calculation efforts for large contact areas. Two objectives are pursued with the targeted meshing strategy: on the one hand, the necessary resolution for measured surface structures can be realized; while on the other hand, the total number of elements is reduced by a coarse grid in the surrounding areas. In this way, rolling–sliding contacts with large contact areas become computable with conventional simulation computers. Using the newly developed “method of combined solutions,” the overall result is finally composed by the combination of section of separate solutions, which are calculated by consecutively shifting the finely meshed segment over the entire contact area. The vital advancement in this procedure is the introduction of irregular grids, through which the cross influences are not neglected and fully regarded for every separate calculation. The presented methodology is verified stepwise in comparison to the Hertzian theory. The influence of irregular grids on the calculation quality is examined in particular. Finally, the calculation approach is applied to a real disk-on-disk rolling contact based on measured surface topography.

A Method for Measuring Foot Pressures Using a High Resolution, Computerized Insole Sensor: The Effect of Heel Wedges on Plantar Pressure Distribution and Center of Force

Foot & Ankle ◽  
1992 ◽  
Vol 13 (5) ◽  
pp. 263-270 ◽  
Author(s):  
Nicholas E. Rose ◽  
Lawrence A. Feiwell ◽  
Andrea Cracchiolo
Keyword(s):  
High Resolution ◽  
Pressure Distribution ◽  
Plantar Pressure ◽  
Foot Pressure ◽  
The Third ◽  
Plantar Pressures ◽  
Pressure Sensitive ◽  
Plantar Pressure Distribution ◽  
Normal Test

A new, high resolution, pressure-sensitive insole was tested and found to provide reproducible measurements of static and dynamic plantar pressures inside the shoe of normal test subjects under certain conditions. However, calibration between separate sensors was poor and the sensor pads showed significant wear with use. This system was also used to investigate the effect of heel wedges on plantar foot pressure to determine whether this system was sensitive enough to detect the effect of a gross shoe modification on plantar foot pressure. Medial heel wedges decreased plantar pressures under the first and second metatarsals as well as under the first toe, and shifted the center of force laterally in all portions of the foot. Lateral heel wedges decreased pressures under the third, fourth, and fifth metatarsals, increased pressures under the first and second metatarsals, and shifted the center of force medially in all portions of the foot. Our evaluations indicate that it is possible to measure static and dynamic plantar foot pressures within shoes and to study the possible effect of shoe modifications on plantar pressures in controlled gait trials.

Observations of the spatial structure of interstellar hydrogen

1967 ◽  
Vol 31 ◽  
pp. 45-46
Author(s):  
Carl Heiles
Keyword(s):  
High Resolution ◽  
Spatial Structure ◽  
Velocity Dispersion ◽  
Temperature Variations

High-resolution 21-cm line observations in a region aroundlII= 120°,b11= +15°, have revealed four types of structure in the interstellar hydrogen: a smooth background, large sheets of density 2 atoms cm-3, clouds occurring mostly in groups, and ‘Cloudlets’ of a few solar masses and a few parsecs in size; the velocity dispersion in the Cloudlets is only 1 km/sec. Strong temperature variations in the gas are in evidence.

Combining integrated systems-biology approaches with intervention-based experimental design provides a higher-resolution path forward for microbiome research

2019 ◽  
Vol 42 ◽  
Author(s):  
J. Alfredo Blakeley-Ruiz ◽  
Carlee S. McClintock ◽  
Ralph Lydic ◽  
Helen A. Baghdoyan ◽  
James J. Choo ◽  
...  
Keyword(s):  
Systems Biology ◽  
High Resolution ◽  
Experimental Design ◽  
Integrated Systems ◽  
Microbiome Research ◽  
Constructive Criticism

Abstract The Hooks et al. review of microbiota-gut-brain (MGB) literature provides a constructive criticism of the general approaches encompassing MGB research. This commentary extends their review by: (a) highlighting capabilities of advanced systems-biology “-omics” techniques for microbiome research and (b) recommending that combining these high-resolution techniques with intervention-based experimental design may be the path forward for future MGB research.

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