67results about How to "Flying low" patented technology

Provided is a magnetic disk comprising a lubricating layer formed of a lubricant. The lubricant constituting the lubricating layer has excellent properties, for example, excellent fluidity, surface energy, and CFT properties. By virtue of the excellent properties, the magnetic disk has a high level of reliability despite a low flying height of a magnetic head due to a recent rapid increase in recording density and a very severe environment resistance requirement due to diversification of applications. The magnetic disk comprises a substrate and at least a magnetic layer, a protective layer, and a lubricating layer provided in that order over the substrate. The lubricating layer is formed of a lubricant that is a mixture of a specific perfluoropolyether lubricant with a lubricant formed of a compound comprising perfluoropolyether groups having a perfluoropolyether main chain in the structure thereof and having a hydroxyl group at the end thereof, the perfluoropolyether groups being bonded to each other through a divalent linking group having at least two hydroxyl groups in the structure thereof.

A compression zone recording head is provided having the recording tape in contact or near contact with the recording read / write transducer elements in a compression zone of the tape passing over a transducing surface. The compression zone recording head comprises a flat or shallow contour head having a thin, hard, preferably conducting closure to provide wear protection to the transducers. In one embodiment of the invention, the transducers are located in a compression zone region where the recording tape contacts an edge of the transducing surface at a controlled wrap angle. In another embodiment, the transducers are located in a canopy zone region of the transducing surface due to bending of the tape due to the overwrap. The protective closure is preferably made of sputter deposited Al—Fe—Si, or alternatively of a deposited or bonded layer of Al—Fe—Si, Al—O—Ti—C, Zr—O—Ti, Si—N, Si—C or Zr—O.

A slider of a magnetic head device has a side that faces a recording medium and on which a first positive pressure is exerted on the leading side and a second positive pressure is exerted on the trailing side. In the area between the first positive pressure area and the second positive pressure area, a small second negative pressure is created at the front, a first negative pressure larger than the second negative pressure is created at the rear, and a third positive pressure is exerted on both sides of the first negative pressure area. When air density decreases, the small second negative pressure in a middle area and the large first negative pressure at the rear of the second negative pressure area stabilize the pitch angle of the slider and prevent an excessive decrease in the flying distance of a trailing end portion.

The invention discloses a chlorophyll content estimating method for winter wheat in a returning green stage. The method comprises the following steps: acquiring an actually measured value of the chlorophyll content of the winter wheat in the returning green stage at a sampling point; acquiring a multispectral remote sensing image of the sampling point, shot and transmitted by an unmanned aerial vehicle; pre-processing the multispectral remote sensing image to obtain a wave band image of which an image reflectivity is within a preset threshold value; extracting a reflectivity value of each waveband of a pixel corresponding to the sampling point from the wave band image; performing correlation analysis on the actually measured value of the chlorophyll content and the reflectivity value of each wave band by using a statistics product and service solution method, to obtain a sensitive wave band; through a multiple linear regression method, constructing chlorophyll content estimating models; screening the chlorophyll content estimating models to obtain an optimal estimating model; and estimating the chlorophyll content of the winter wheat in the returning green stage in an area to be tested by using the selected optimal estimating model. The provided chlorophyll content estimating method based on the multispectral image of the unmanned aerial vehicle is capable of solving the problems that an existing method wastes time and energy, the time stability is poor,and a spatial resolution is low, and the like.

The invention provides an agricultural plant-protection levitation-type flight work platform, which solves the problems of the existing aircraft that the safety coefficient is not high and safety potential danger exists. The agricultural plant-protection levitation-type flight work platform comprises a levitation lifting body, a propelling part and a lifting part, wherein the lifting part is embedded in a central duct of the levitation lifting body and used for adjusting the operation height of the work platform in real time; and the levitation lifting body is connected with the propelling part, and the propelling part is used for supplying thrust and steering force needed by the flight. The agricultural plant-protection levitation-type flight work platform has the advantages of safety in use, low flight height, controllability in flight speed and suitability for distributing the plant-protection preparation and can prevent the problems such as the threat of facilities or personnel on the ground brought by the flight accident easily caused by the low safety coefficient and safety potential danger of the existing aircraft in the flight process; and through the control of a uniform command of a subarea control station, on the premise that the normal operation effect of the agricultural facilities is not influenced, completely-unmanned and automatic high-efficient agricultural plant-protection operation can be effectively realized.

A perpendicular magnetic recording medium has a substrate, a soft magnetic underlayer formed on the substrate, arrayed soft magnetic dots formed on the soft magnetic underlayer, and a ferromagnetic recording layer formed on the soft magnetic dots and having magnetic anisotropy in a direction perpendicular to a surface of the substrate.

A method for burnishing a slider in a disk drive in which the disk is rotated in the opposite or reverse direction from that used to develop the air-bearing and to read and write data is described. Rotating the disk in the reverse direction results in no air-bearing being formed and the slider being in contact with the disk surface. The burnishing removes material over the magnetic transducers in the slider which separate the transducers from the disk resulting in greater sensitivity. Optionally the stopping point for burnishing can be determined by monitoring measurable parameters such as the change in the MR resistance (MRR), i.e., ΔMRR / MRR until a selected range is achieved. The invention can be used to remove an overcoat from the air-bearing surface of the slider, remove protruding areas from the slider and to remove debris from the disk surface.

The proportion of {100} crystal faces, the polish rate of which is relatively high during crystal machining, and / or the proportion of {111} crystal faces, the polish rate of which is relatively low during crystal machining, to the total area (S0) of a substrate surface, is set to fall within an appropriate range. Specifically, the proportion of the total area (S{100}) of the {100} crystal faces among crystal faces of individual crystal grains which appear on a major surface of a polycrystalline silicon substrate to the total area (S0) of the substrate surface, is set not less than 10% and less than 50%. Such crystal face selection makes it possible to reduce the scale of “steps” formed due to the crystal face index dependence of polish rate, thereby to give a planar and smooth substrate surface.

A magnetic head device is provided. A slider of a magnetic head device has a side that faces a recording medium and on which a first positive pressure is exerted on the leading side and a second positive pressure is exerted on the trailing side. In the area between the first positive pressure area and the second positive pressure area, a small second negative pressure is created at the front. A first negative pressure larger than the second negative pressure is created at the rear. A third positive pressure is exerted on both sides of the first negative pressure area. When air density decreases, the small second negative pressure in a middle area and the large first negative pressure at the rear of the second negative pressure area stabilize the pitch angle of the slider and prevent an excessive decrease in the flying distance of a trailing end portion.

The invention is directed to a magnetic head driving circuit and a magnetic disk device which achieve a low flying-height with thermal protrusion and thus a reliable write operation on the magnetic disk. The write circuit 3 receives the write data signal Sw inputted therein, and generates and outputs the write voltages Wx, Wy based upon the inputted signal. The write voltages Wx, Wy are composed of a preamble portion T1, a sink mark T2 and a user data portion T3 in each sector for magnetic recording. In the write voltage, the frequency f2 of the signal in the preamble portion T1 is higher than half the frequency f1 of the signal in the user data portion T3.

Embodiments of the present invention provide a head slider that suppresses accumulation of lubricant droplets on an air-bearing surface due to a backflow, and thus improves reliability of a disk drive. According to one embodiment, a lubricant droplet being adhered to a head slider and accumulated thereon, which are caused by extremely low flying height of the head slider, are prevented from falling onto a recording medium. When velocity of a recording medium at a position where the head slider faces the recording medium is assumed to be v, step depth δ4 at an outflow side of an outflow side rail satisfies, δ4≦0.1125*log10(v)+0.019.

A method of manufacturing a glass substrate for a magnetic disk includes a polishing step of polishing a main surface of a glass substrate by sandwiching the glass substrate between a pair of surface plates each having a polishing pad on its surface and by supplying a polishing liquid containing polishing abrasive particles between the glass substrate and the polishing pads. In the polishing step, the polishing liquid and each polishing pad are adjusted so that the friction coefficient falls in a range of 0.02 to 0.05.