268 results about "Dihedral angle" patented technology

An airfoil for a compressor is described. The airfoil has a root, an airfoil tip, a leading edge, a trailing edge, airfoil pressure and suction sides extending between the leading edge and the trailing edge. The airfoil has an inner span region and an outer span region and the trailing edge has a dihedral profile such that the trailing edge dihedral angle decreases in at least a portion of the inner span region and the outer span region.

A laser amplifier includes a laser active slab with a source of pump power to amplify an input laser beam, the laser active slab including a block of laser active material having opposed lateral faces defining a wedge lateral dihedral angle, opposed longitudinal faces, and opposed parallel transverse faces, the wedge lateral dihedral angle specified to minimize parasitic amplified spontaneous emission. The source of pump power may be one or more laser diode bars and microlenses producing a gain sheet in the laser active slab. The lateral faces may include optical coatings highly transmitting at a wavelength of the pump power and highly reflecting at a lasing wavelength to provide a folded path for the input laser beam though the gain sheet. The laser amplifier may optionally include one or more external mirrors highly reflecting at the lasing wavelength positioned and oriented to provide one or more additional zig-zag passes through the gain sheet for the input laser beam and to provide a multi-pass-amplified laser beam.

The invention relates to a prosthesis that can be implanted in the centre of wall wound scarring. The inventive prosthesis, which is intended for use in abdominal surgery, is provided with a geometric shape in the form of sheets that converge in dihedral angles. The sheets or planes are made from a synthetic biotolerated material in porous form with large pores. One of said planes is inserted into the centre of the scarring between the two aponeurotic surfaces to be joined. The other plane(s) of the prosthesis, which is perpendicular to the aforementioned plane, is arranged so as to overlap the aponeurotic edges of the edge of the section. The proliferation obtained around the prosthesis, in the scarring centre and close thereto, provides stress resistance greater than that obtained in standard closures, thereby greatly reducing the risk of hernias caused by a badly healed wound.

In short, the Eolic Marine Electrical Generator "GEEM" is an extraordinary invention used for capturing the huge impulse force of water or wind, to generate mechanical energy and to transform the mechanical energy into electrical energy, clean and ecological, without consuming vital oxygen thanks to the invention of immense split, self-regulating panels, radially fixed in dihedral angle to a rotary central shaft, panels which capture by shock the inexhaustible energy of the wind, the waves or the ocean currents; or fixed on rotary or flying machines of high speed, with panels formed at the same time by oscillating vanes that at a certain time of a turn of 360° will face the natural energy as a single group or panel, capturing therefrom the impulse force and converting it into rotary movement through the central rotary shaft. Said vanes in other rotation, by oscillation, will divide the panel and will align themselves with the natural vector, permitting its free passage, eliminating the turning resistance of the panel against water or wind and generating a constant rotation movement, independent of the direction of water or wind, and then transforming said mechanical energy into electrical energy by existing conventional means. The invention will allow men to renew their resources and to obtain electrical energy from anywhere in the planet such as cities, countryside, deserts, forests, mountains, seas, floating cities or spaces such as the Arctic and the Antarctic, neither polluting the environment, nor depending on costly networks or non-renewable inputs. The invention will also generate electrical energy on fleets, land vehicles or airship without consuming non-renewable fuel or destroying oxygen. Moreover, this invention replaces the internal combustion engines by eolic electrical motors, changing the scenery of the modern world and recovering the ozone lost in the Antarctic. And this invention will also be used when men in future colonize planets, without rivers or seas but with plenty of wind, to generate electrical energy without polluting this new vital space of the human race.

A rotor blade for a gas turbine engine includes an airfoil that extends in span between a root and a tip region. A leading edge and a trailing edge of the airfoil section extend between a chord line of the airfoil. A sweep angle is defined at the leading edge of the airfoil section, and a dihedral angle is defined relative to the chord line of the airfoil section. The sweep angle and the dihedral angle are localized at the tip region of the airfoil section.

A submersible vehicle for use in a body of liquid includes a vehicle body, a pair of fins coupled to the vehicle body on opposed sides thereof, and a dihedral angle control system. The dihedral angle control is system operative to vary a fin dihedral angle of each of the fins.

3D mesh models are widely used in various applications for representing 3D objects. These models are made of vertices and corresponding triangles, which can be compressed based on prediction and residuals. The present invention improves the accuracy of parallelogram prediction, particularly near sharp features. The proposed 3D mesh model encoding comprises analyzing the spatial or dihedral angles between triangles, clustering triangles with similar or equal dihedral angles, and defining a representative dihedral angle for each cluster. Triangles of each cluster are then encoded relative to individual prediction triangles having the representative dihedral angle according to the cluster. Additionally, the prediction triangle may be mirrored. An indication of the encoding mode is inserted into each vertex of the encoded bitstream. A decoder extracts the encoding mode indication, reconstructs the individual prediction triangles based on the respective representative dihedral angles and performs triangle prediction and reconstruction.

The invention discloses a Freeman decomposition and homo-polarization rate-based polarized synthetic aperture radar (SAR) image classification method for mainly solving the problems of higher calculation complexity and poor classification effect in the prior art. The method comprises the following steps of: (1) inputting a covariance matrix of polarized SAR data; (2) performing Freeman decomposition on the input matrix to acquire three types of scattering power matrixes of plane scattering, dihedral angle scattering and volume scattering; (3) performing initial division on the polarized SAR data according to the three types of scattering power matrixes; (4) calculating the homo-polarization rate of all pixel points of the polarized SAR data of each class; (5) selecting a threshold value, and dividing the polarized SAR data of each class in the step (3) into 3 classes according to the homo-polarization rate, so that the whole polarized SAR data are divided into 9 classes; and (6) performing repeated Wishart iteration and coloring on the division result of the whole polarized SAR data to obtain a final color classification result graph. Compared with the classical classification method, the method has the advantages that the division of the polarized SAR data is stricter, the classification result is obvious and the calculation complexity is relatively low.

A quadcopter has a fuselage and four rotors, each defining a thrust vector. An onboard camera system includes a gimbal with a roll axis and a pitch axis. Right side motors are mounted with a dihedral angle so that their respective thrust vectors intersect at a common focal point located above the fuselage. Left side motors are mounted with a dihedral angle so that their respective thrust vectors intersect at a common focal point located above the fuselage. The tilted thrust vectors provide yaw stability which allows flight yaw control to be used as yaw control of the onboard camera.

The electrocardiograph (200) of the invention is suitable for capturing a twelve-lead electrocardiogram from signals representative of the cardiac activity of a patient and acquired with the help of at least nine electrodes. The electrocardiograph comprises a body (210) having a front face (211) and at least one arm (212, 213) suitable for being folded beside the body and pivotable about an axis that is substantially parallel to the front face. Each arm is adapted to form a variable dihedral angle with the front face so that the substantially concave surface (214) formed by the front face and the or each arm and having six precordial electrodes (201-206) distributed thereon, is capable of adapting to the patient's morphology so as to enable the precordial electrodes to be properly positioned on the patient's chest. The electrocardiograph also includes means enabling said good positioning of the precordial electrodes on the patient's chest to be maintained.

A boat propeller includes a hub having a front, back, and an axis of revolution extending therebetween. A plurality of blades provide and extend from the hub between the front and back. Each blade includes a surface adjacent of the hub disposed at an oblique angle to the hub axis and a blade tip having an adjacent surface forming a dihedral angle with a surface adjacent to the hub extended on the forward camber only. The surface adjacent to the blade tip is inclined at a greater angle to the hub axis than the surface adjacent to the hub. Each blade includes a trailing edge extending radially from the hub with each trailing edge being substantially straight and a tip is provided joining the trailing edges at approximately a 90° angle. An arcuate leading edge is provided between each blade tip and a hub and a flange is disposed on each blade tip and extends parallel to the hub axis toward the hub back.

The invention provides a special fixture used for processing an open slot on a spatial dihedral angle slope of a turbine blade, and the special fixture is characterized by comprising a slope baseboard component capable of adjusting a radial gradient, wherein a tailstock tip component and an end face positioning component are oppositely arranged at two radial ends of the slope baseboard component; a slope cushion component which is capable of adjusting an axial gradient and a height is arranged on the slope baseboard component between the tailstock tip component and the end face positioning component; a side wall positioning component is also arranged on the slope baseboard component; the side wall positioning component can axially feed a side wall positioning element which is contained in the side wall positioning component; a clamping component is also arranged on the slope baseboard component; and a pressing head capable of feeding downward is arranged at the tail end of the clamping component. The fixture provided by the invention can firmly and accurately position a device, can quickly and efficiently process the open slot meeting a design demand on a size precision and a position precision, and has ultrahigh surface glossiness.

The invention discloses a polarization four-component decomposition method for a city area. The method comprises the following steps of: performing preprocessing on the polarimetric synthetic aperture radar image data of the city area so as to obtain a coherent matrix T theta; S12: eliminating the orientation angle theta in the coherent matrix T theta so as to obtain coherent matrix T; and S13: performing polarization four-component decomposition on the coherent matrix T by using a volume scattering model Tv. Through the orientation angle compensation performed on a coherent matrix and using a new volume scattering model to describe the volume scatting in polarization decomposition, the negative power problems of surface scattering and dihedral angle scattering, which are caused by overestimated volume scattering power, can be released to a certain extent.

The present invention relates to a retroreflective article enabling to retroreflect incident light in its incident direction, and the retroreflective article including at least one retroreflective element, the retroreflective element comprising at least one reflecting corner comprised of a pair of corner reflecting surfaces which meet at dihedral angle of about 90 degree; and a pair of vertical reflecting surfaces which are formed on both ends of the reflecting corner to be substantially perpendicular to a corner of the reflecting corner with a distance which is smaller than the highest vertical height and which meet at dihedral angle of about 90 degree for the pair of corner reflecting surfaces. This retroreflective article has higher retroreflective ratio and wider available retroreflective range, and it is designed to be freely changed its main reflecting direction having the highest retroreflective ratio.

The invention discloses a background extraction and offset processing method for RCS (Radar Cross Section) measurement of a low detectable target. The method can cover, but is not limited to, the existing operation including rectilinear translation of an auxiliary measurement carrier, azimuth rotation of an eccentric cylinder or rotation measurement of a dihedral angle reflector around a radar sight line. According to the method, a fixed background can be extracted by utilizing measurement data of various different auxiliary measurement bodies, thereby greatly expanding the application range of auxiliary background measurement, background extraction and offset technologies in the RCS measurement of the low detectable target. Particularly, when double-calibration bodies serve as the auxiliary measurement bodies, calibration measurement and auxiliary background extraction measurement can be simultaneously completed at a time; when targets self serve as the auxiliary measurement bodies, target measurement and auxiliary background extraction measurement are simultaneously completed at a time. According to the method, the measurement process and the workload are greatly simplified, and the problem of non-ideal background offset processing effect caused by the factors such as shifting of a measurement system is further solved.

A process for the carbonylation of a conjugated diene, which involves reacting the conjugated diene with carbon monoxide and a co-reactant having a mobile hydrogen atom in the presence of a catalyst system including: (a) a source of palladium; and (b) a bidentate diphosphine ligand of formula II,

R¹R²>P¹—R³_m—R—R⁴_n—P²<R⁵R⁶   (II)

wherein P¹ and P² represent phosphorus atoms;

R¹, R², R⁵ and R⁶ independently represent the same or different optionally substituted organic radical containing a tertiary carbon atom through which each radical is linked to the phosphorus atom;

R³ and R⁴ independently represent the same or different optionally substituted methylene groups;

R represents an organic group having the bivalent bridging group C¹—C² through

which R is connected to R³ and R⁴;

m and n independently represent a natural number in the range of from 0 to 4, wherein the rotation about the bond between the carbon atoms C¹ and C² of the bridging group is restricted a temperature in the range of from 0° C. to 250° C., and wherein the dihedral angle between the plane occupied by the three atom sequence composed of C¹, C² and the atom directly bonded to C¹ in the direction of P¹, and the plane occupied by the three atom sequence C¹, C² and the atom directly bonded to C² in the direction of P², is in the range of from 0 to 120°; and

(c) a source of an anion.

A structured abrasive article comprises a backing, and an abrasive layer disposed on and secured to the backing. The abrasive layer comprises shaped abrasive composites, each comprising abrasive particles dispersed in a binder. Each the shaped abrasive composites independently comprises: a base disposed on the backing; a plurality of walls extending away from the base, and a grinding surface not contacting the base. Adjacent walls share a common edge. Each wall independently forms a dihedral angle with the base of less than or equal to 90 degrees. The grinding surface has a plurality of: cusps, and facets that contact a recessed feature. At least a portion of the recessed feature is disposed closer to the base than each of the cusps. Each cusp is formed by an intersection of two of the walls and at least one of the facets. Use of the structured abrasive article to abrade a workpiece is also disclosed.

A rotary-wing includes a multi-hedral tip section which utilizes a distribution of anhedral and/or dihedral angles that cause a tip vortex to be axially displaced relative to a region on a following blade such that the tip vortex generally avoids influence upon the following blade.

An improved combination holder and coaster apparatus for receiving a container or vessel which includes first and second thermally insulative, flexible panels joined together by a joint comprised of a stretchable, flexible, adhesive material adapted to return the device to a collapsed coaster configuration. While in receipt of the vessel or container, the device is adapted to an elliptical holder configuration in which the panels are separated by a projected dihedral angle generally between approximately 0 degrees through approximately 180 degrees allowing the elliptical holder to receive the vessel or container.

An ultrasound emitting device is disclosed. The ultrasound emitting device includes a sound head matrix comprising a first planar member, and a second planar member, wherein the first planar member is attached to the second planar member to form a V-shaped assembly comprising a first interior dihedral angle, where that first interior dihedral angle is between about 155 degrees and about 175 degrees. The ultrasound emitting device further comprises a first plurality of ultrasound transducers disposed on the first planar member, and a second plurality of ultrasound transducers disposed on the second planar member.