"Feel For The Water": What Is It, Really?

Science NewsVolume 179, Issue 5 p. 10-10 In the News Body & brain: Helping artificial limbs to feel real: Prosthetics with a ‘sense of touch’ more like part of body Laura Sanders, Laura SandersSearch for more papers by this author Laura Sanders, Laura SandersSearch for more papers by this author First published: 18 February 2011 https://doi.org/10.1002/scin.5591790509AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume179, Issue526 February 2011Pages 10-10 RelatedInformation

It is known that the brain uses the sense of touch, in different parts of the body, to acquire information to react to the environment. With nowadays technology, it is possible to create distinct virtual environments and to feel them with haptic devices. Using haptic devices, it is possible to train and develop different parts of the human body, including the brain. These devices allow users to feel and touch virtual objects with a high realism. The present paper proposes different controller methods to use a haptic device to help the user to exercise their hands. The hand exercises proposed are the straight-line, square, circle and ellipse follow-up. In this work four different types of controllers are compared: proportional, proportional-derivative and logarithmic and sigmoid function based controllers. Each one of the used controllers were tested with the hand exercises mentioned. The sigmoid and logarithmic function based controllers achieves more suitable results for the user haptic perception and trajectory follow-up.

Your brain can be divided into various areas, one of which is responsible for your sense of touch. This part of your brain can be divided into even smaller areas that communicate with each body part. We can use a special map of the human body, called a sensory homunculus, to help us understand the various sizes of these parts of the brain. We will explain how this map was created and tell you about research showing how these brain areas can change. One study showed that brain areas can be recycled, meaning that the brain areas that no longer receive messages from the body can be used by other functioning brain areas. Another study showed that these changes can even occur within a single day! These studies can help scientists to better understand the brain and to help people who have problems with the sense of touch.

Effects of gravity and pressure on laminar coflow methane–air diffusion flames at pressures from 1 to 60 atmospheres

Effect of the Reynolds and Richardson numbers on thermal mixing characteristics

Phase separation is a well-known effect in liquid-liquid interactions, which can also occur during laser-related processes such as laser melting and laser alloying. However, the mechanism of phase separation between immiscible liquids on a millimeter scale during rapid laser processes has not been fully investigated, in which the extent of buoyancy’s contribution to it has remained unclear. Therefore, this investigation focused on the effect of buoyancy on liquid phase separation during the laser melting of silicon (Si) and iron ore. A simplified 2D numerical model was established to simulate the motion of a single Si liquid droplet in iron ore melt with and without the impact of gravity, respectively. The rise velocity of the droplet was calculated and analyzed under the effect of gravity. In addition, the phenomena of simultaneous laser remelting of Si and iron ore in layers were recorded with a high-speed camera, and the element and phase distributions of the target nugget were analyzed by Scanning Electron Microscopy/Energy Dispersive Spectroscopy (SEM/EDS). By combining the simulation, high-speed imaging, and SEM/EDS analysis, the effect of buoyancy on phase separation has been qualitatively analyzed. This investigation revealed that buoyancy is not the main driving force of liquid-liquid phase separation during rapid laser processing.

Touch is the sense of direct contact The verb ‘to touch’ can be used in two ways. We can say that a bottle touches the table. By this we may mean that the bottle is in direct contact with the table, that there is nothing in between the two. However, when I say that I touch the hardness of the table I may mean something different, namely, that I feel or perceive the hardness of the table. I touch the table in this way only when I am using my sense of touch. Similarly, we can say that the touch of your hand is cold. In that case too it is implied that I perceive your hand as cold by my sense of touch. Perhaps it is more usual to use the verb ‘to feel’ rather than the verb ‘to touch’ as a verb of perception. One would say ‘I feel the hardness of the table’ rather than ‘I touch it’ if one wants to say that I perceive the table rather than that I am simply leaning on it with some part of my body. That is perhaps also why it seems more natural to use the verb ‘to touch’ when the idea is just that there is contact between two things and no perception takes place.

The sense of touch provides humans with the ability to determine the shape and surface properties of objects. Although touch is an important part of daily life for object manipulation and exploration tasks, users are, unfortunately, rarely provided with the opportunity to use their sense of touch while interacting with computers. To rectify this, this article presents a novel haptic mouse system that can be used as a human-computer interface with the capability for holistic haptic feedback, including contact force, surface properties, and thermal feedback. The system is composed of 3 main parts. First, the 5-bar mechanism, which comprises the lowermost part of the mouse's body, has been adapted to realize 2-DOF translational force feedback. This mechanism helps the user to feel the contact force, stiffness, and size of a virtual object while exploring a graphical environment. Second, a small tactile display was developed. It has a planar-distributed pin array, and it can represent microscale shapes with various surfaces, such as gratings, grooves, patterns, shapes of icons, and Braille, thereby providing the user with cutaneous stimuli. Third, because the ability to sense temperature is an important factor in the discrimination of the surface property of an object, thermal feedback is provided to the user. The performance of each part and their combinations has been evaluated, and the system shows a remarkable ability to provide users with tactual information while they simply use the mouse without any additional interfaces.

The production of crystals of adequate size and high quality is the bottleneck for three- dimensional structure analysis of protein crystals. In this work, in order to shed additional light on the (still controversial) beneficial effect of microgravity on crys- tal growth, we focus on recent advanced experimental and theoretical research about the effects of buoyancy- driven convection on protein crystallization. In the light of the numerical studies the following major outcomes can be highlighted: (1) when the crystal size exceeds several dozens of µm, buoyancy-driven convection dom- inates solute transport near the growing crystal and the crystal growth rate becomes larger than that under zero gravity. (2) The ratio of the side-surface growth rate to the top-surface growth rate increases with crystal size be- cause of convection and the ratio is about three when the crystal size is 100 µm. The ratio of the side-surface growth rate to the top-surface growth rate measured ex- perimentally confirms these results (the averaged value for 127 protein crystals was determined to be about two). Thus, both numerical and experimental studies provide a solid basis to the idea that convection strongly affects the crystal growth rate. Moreover, since according to experiments about the dependence of crystal quality on effective gravity (hypergravity or microgravity obtained by means of magnetic field gradients), protein crystals (e.g., orthorhombic lysozyme or snake muscle fructose- 1,6-bisphosphatase) exhibit better quality with decreas- ing the gravity level, buoyancy-driven convection may be thought of as also affecting crystal quality in a detrimen- tal way.

The concentrated solar thermal systems, operating in the medium temperature range of 373–573 K, will be extremely useful for several industrial processes. However, the need for an in-depth understanding of the turbulent heat transfer in parabolic trough absorbers with pure and hybrid nano-oils, including the effect of buoyancy or gravity, is realized. This paper presents the Reynolds-averaged Navier–Stokes (RANS)-based turbulent heat transfer analyses in a 3D, long, straight for Reynolds number from 5000 to 20,000 and discrete heating conditions with different heat flux ratios such as 1, 5, 10, 20, 40, and 50 for pure oil and hybrid nano-oils having 1, 4, and 6% volume concentration of the nanoparticles. The major findings are, (a) gravity-induced anisotropy leads to high and low-speed fluid flows near the lower and upper walls, and temperature redistribution at a plane, which is beneficial, (b) the statistical axial-velocity deviates from the standard logarithmic law at a Reynolds number of 5000, and (c) the ratio of surface-area-averaged Nusselt number between the lower half and upper half of the tube is 4–12. Some important recommendations are (a) the effect of gravity must be included, (b) the local Richardson number may be used for improving the standard logarithmic law for the axial velocity, and (c) Nusselt number correlations are deduced for the upper half surface and lower half surfaces. The findings, albeit for limited parameters, will be useful for improving the heat transfer aspects in the parabolic trough absorber.

Human Performance in Altered-Gravity Environments

Numerical study of effects of stand-off distance and gravity on large scale bubbles near a breach

Decision letter: Spinosaurus is not an aquatic dinosaur

In this paper, vibration signals are investigated. Vibration signal is a vibration we use with special purposes or intentions. Vibration signal can transmit information to person through the sense of touch. Vibrators of portable phones are one kind of examples. The purpose of this study is to research on human sensitivity by vibration frequency, vibration pattern and parts of body that receive signals, and to propose the most suitable vibration signal for information. At First, 5 trial vibration signals refering to clock alarm, oven, rice cooker, and public phone sounds were made to find out the most conscious vibration signal. These vibration signals were evaluated by using SD method and the factor analysis. And, the clock alarm type vibration signal was obtained to be the most conscious vibration among the vibrations adopted in this report. Then this signal was modified and compared with the original one. The suitable vibration signal for forefineer was found.

This paper presents a generalized mathematical model that comprehensively characterizes the flow behavior of matrix nanopores and natural/hydraulic fractures in tight oil reservoirs during spontaneous imbibition. The model incorporates various influencing factors such as fracture distribution, displacement pressure gradient, gravity, and buoyancy. The complex pore structure of tight oil reservoirs, including nanopores and natural microfractures, presents a challenge in developing an accurate mathematical model for predicting flow behavior. The proposed model considers the fractal characteristics of pores and fractures and accounts for many factors to predict cumulative oil production, oil flow rate, and oil recovery factor during imbibition flow. Experimental data on fractured tight sandstones are used to validate the model, and sensitivity analyses are conducted to assess the influence of pore structure parameters, fracture distribution, and fluid properties on imbibition behavior. The findings reveal that gravity and buoyancy effects become more prominent under low interfacial tension. Fracture distribution significantly impacts imbibition behavior, with critical values for fractal dimensions, fracture numbers, and apertures determining the extent of their influence. Higher contact angles and increased oil phase viscosity result in reduced imbibition efficiency. In pressure-driven displacement processes, larger fractures preferentially produce crude oil, and the higher pressure gradients result in shorter imbibition processes. The proposed model offers insights into the imbibition oil recovery mechanism in tight oil reservoirs and can contribute to improved recovery factors.