333 results about "Surface matching" patented technology

Improved, adaptable tissue-type heart valves and methods for their manufacture are disclosed wherein a dimensionally stable, pre-aligned tissue leaflet subassembly is formed and its peripheral edge clamped between and attached to an upper shaped wireform and a lower support stent. A variety of adaptable structural interfaces including suture rings, flanges, and conduits may be attached to the support stent with or without an outlet conduit disposed about the wireform to provide a tissue-type heart valve adaptable for use in either a natural heart or in mechanical pumping devices. The methods include forming individual leaflets with a template and using the template to attach the leaflets together to form a tissue leaflet subassembly. The template and leaflets include a straight edge terminating in oppositely directed tabs, and a curvilinear cusp edge extending opposite the straight edge. The template may include a guide slot in its straight edge and the assembly includes aligning two leaflet tabs with the template and passing sutures through the guide slot and through the leaflet tabs. The leaflet subassembly is mated to a wireform with the tabs extending through commissure posts of the wireform. A support stent having an upper surface matching the lower surface of the wireform sandwiches the edges of the leaflet subassembly therebetween. Separated tabs on the leaflet subassembly are passed through the wireform commissures and attached to adjacent stent commissures so as to induce clamping of the leaflet tabs between the stent commissures and wireform commissures upon a radially inward force being applied to the leaflets.

A method and apparatus for use in a subterranean well is described. The apparatus typically includes a mandrel and a packing element. The mandrel may have an outer surface and a non-circular cross-section and the packing element may be arranged about the mandrel, the packing element having a non-circular inner surface matching the mandrel outer surface such that concentric rotation between the mandrel and the packing element is precluded. The apparatus may include slips having cavities to facilitate removal of the apparatus. The apparatus also may include a valve for controlling upward fluid flow through a hollow mandrel. The valve may include a flapper having at least one tab to engage at least one recession in the mandrel such that rotation between the mandrel and the valve is precluded when the valve is in a closed position. The apparatus may further include a central member which is releaseably attached to the mandrel by a release mechanism.

A device and technique for the preparation and implantation of osteochondral allografts for resurfacing of a human joint. The grafts are prepared to a uniform shell thickness using the described invention.

An electronic cigarette comprising an atomizer and a first case configured for accommodating the atomizer is provided; the atomizer includes a heating mechanism, a breather pipe, and oil storage cotton, the heating mechanism is received inside the breather pipe, and the oil storage cotton envelops an outer surface of the breather pipe; wherein, the heating mechanism is positioned along an axial direction of the breather pipe, and has a shape matching an inner surface of the breather pipe. The heating mechanism in the electronic cigarette has a large effective heating area so that more smoke can be generated by the atomizer.

A segmented pulley transmission [20] is provided. A pulley assembly [36] is rotationally mounted on an axle [32]. The pulley assembly [36] includes a core pulley [45] having a first set of mating features on a peripheral surface thereof. A pulley segment set comprises a number of pulley segments [48] slidably mounted in the pulley assembly and arranged in a ring concentric with the core pulley [45]. The pulley segments [48] are individually actuatable out of the pulley assembly into an engaging position and into the pulley assembly into a non-engaging position. The pulley segments [48] have a second set of mating features [52] on an peripheral surface matching the first set of mating features. An endless drive member [47] has corresponding mating features on an inside surface for engaging the first and second sets of mating features of the core pulley [45] and the pulley segments [48] in an engaging position. Contact between the endless drive member [47] and a core pulley defines a contact zone [CZ]. An actuator [80] actuates the pulley segments [48] between the engaging and non-engaging positions when the pulley segments [48] are outside of the contact zone [CZ]. One of the pulley segments [48] in the pulley segment set is a key pulley segment [48a] that is positioned relative to the care pulley [45] such that when the key pulley segment [48a] is actuated to the engaging position and rotated into the contact zone [CZ], the corresponding mating features of the endless drive member [47] engage the first set of mating features of the core pulley [45] and the second set of mating features [52] of the key pulley segment [48a] without the introduction of significant slack or tension.

The invention provides an ultrasonic training system based on CT (Computed Tomography) image simulation and positioning. Ultrasound image simulation and CT volumetric data rendering are accelerated to be achieved through a GPU (Graphics Processing Unit) and the real-time performance of the system is improved. A curved surface matching module is used for performing surface matching on read human body CT volumetric data and physical model data with a physical model as the standard and achieving elastic transformation of a curved surface based on an interpolation method of thin plate splines; an ultrasonic simulation probe position tracking module is used for performing real-time calculation on ultrasonic simulation probe positions relative to the physical model by a marking point tracking method and obtaining arbitrary angle CT slice images according to a position matrix; an image enhancement and ultrasonic image simulation generation module is used for improving the vessel contrast ratio in CT images by a multi-scale enhancement method and achieving the ultrasound image simulation based on the CT volumetric data; and an integration display module is used for accelerating to achieve rendering display of the CT volumetric data based on CUDA (Compute Unified Device Architecture) and integrating and displaying ultrasound simulation images and three-dimensional CT images according to the obtained position matrix.

A forming jig includes a grid pattern of support walls arranged on a support base and having upper free ends located along an imaginary curved surface, and modular sectional profile members arranged on the walls to enclose a vacuum chamber within the jig. Grooves, channels and air passages between neighboring profile members communicate into the vacuum chamber. The outer surface of the profile members matches the intended inner surface of a structural component to be fabricated using the jig. In the fabrication process, a film is applied to the outer surface to pre-establish a vacuum, the film is removed while simultaneously a vacuum skin is applied, stringer members are set into the grooves, fiber skin layers are laid up, a sealant is applied around the perimeter, a structural shell is vacuumed onto the skin layers, and then this preformed component is removed from the jig, injected with resin unless the skin layers were pre-impregnated with resin, and cured.