Abstract: Multi-level power converters are disclosed. In one embodiment, a multi-level power converter includes an input for receiving an input voltage and a converter output for providing a variable output voltage. The multi-level power converter includes a plurality of switching circuits. Each switching circuit is connected to the input in parallel with each other switching circuit. Each switching circuit includes an output. Each switching circuit is selectively operable to couple its output to the input voltage or a reference voltage. The multi-level power converter includes a parallel multi-winding autotransformer (PMA). The PMA includes a plurality of windings and a magnetic core having a plurality of magnetically connected columns. Each winding is positioned around a different one of the columns and has a beginning and an end. The output of each switching circuit is coupled to the beginning of a different winding. The end of each winding is connected to the converter output in parallel with each other winding.

Abstract: Various embodiments of the present invention allow for the generation of at least one estimated value of a first parameter that is derived from a regularly measured value of a second parameter. In addition, a single control feedback signal can be adjusted via updating of the estimated and regularly measured values in a control feedback loop. At least one spiral track can be written to storage media based on the single control feedback signal, where the single control feedback signal can be received from an compensating circuit that receives the at least one estimated value of the first parameter, which can refer to position, and the at least one regularly measured value, which can refer to velocity.

Abstract: A light-emitting device includes: a light-emitting stack having an upper surface having a first surface roughness less than 0.2 nm; and an as-cut wafer comprising an irregularly uneven surface facing the light-emitting stack and having a second surface roughness greater than 0.5 ?m.

Abstract: A light-emitting device comprises a substrate; a first semiconductor layer formed on the substrate; a light-emitting layer on the first semiconductor layer; and a second semiconductor layer having a rough surface formed on the light-emitting layer, wherein the rough surface comprises a plurality of cavities randomly distributed on the rough surface, and one of the plurality of cavities has a substantially hexagonal shape viewed from top and a curved sidewall viewed from cross-section.

Abstract: An imaging system used for material discrimination of an objet is provided. The imaging system includes an X-ray source and an imaging sensor. The X-ray source generates multienergy polychromatic X-ray, wherein there is an integral-multiple relationship between the multi-energy-band of the X-ray. The object is placed between the X-ray source and the imaging sensor. The X-ray is transmitted toward and imaged by the imaging sensor through the object. An imaging multi-energy-band of the imaging sensor corresponds to the multi-energy-band of the X-ray.

Abstract: A field emission cathode device includes a cathode electrode. An electron emitter is electrically connected to the cathode electrode, wherein the electron emitter includes a number of sub-electron emitters. An electron extracting electrode is spaced from the cathode electrode by a dielectric layer, wherein the electron extracting electrode defines a through-hole. The distances between an end of each of the sub-electron emitters away from the cathode electrode and a sidewall of the through-hole are substantially equal.

Abstract: Multi-winding magnetic structures and methods of making multi-winding magnetic structures are disclosed. In one embodiment, a multi-winding magnetic structure includes a core constructed of a magnetic material and a plurality of windings. The core includes a core top, a core bottom, and a plurality of columns. The core top has an exterior edge defining a shape of the core top. A central section of the core top has a substantially constant thickness that defines a thickness of the core top. The core bottom is beneath the core top and has an exterior edge defining a shape of the core bottom. A central section of the core bottom has a substantially constant thickness that defines a thickness of the core bottom. The thickness of one of the core bottom and the core top decreases from an edge of its central section to its exterior edge. The plurality of columns extends from the core bottom to the core top and the plurality of windings are wound around the columns.

Abstract: A method for making field emission electron source comprises following steps. An insulating layer is coated on outer surface of a linear carbon nanotube structure. A field emission electron source preform is formed by locating a plurality of conductive ring on outer surface of the insulating layer, wherein the plurality of conductive ring is space from each other, and each conductive ring comprises a first ring face and a second ring face opposite to the first ring face. A plurality of field emission electron source is formed by cutting off the plurality of conductive ring, the insulating layer, and the linear carbon nanotube structure, wherein each field emission electron source comprises at least one conductive ring, and a ring face of the conductive ring, end surface of the insulating layer, and end surface of the linear carbon nanotube structure are coplanar.

Abstract: A field emission electron source includes a linear carbon nanotube structure, an insulating layer and at least one conductive ring. The linear carbon nanotube structure has a first end and a second end. The insulating layer is located on outer surface of the linear carbon nanotube structure. The first conductive ring includes a first ring face 1301 and a second ring face, an end surface of the linear carbon nanotube structure, and the first ring face are coplanar.

Abstract: A method for making field emission electron source comprises following steps. An insulating layer is coated on outer surface of a linear carbon nanotube structure. A field emission electron source preform is formed by locating a plurality of conductive ring on outer surface of the insulating layer, wherein the plurality of conductive ring is space from each other, and each conductive ring comprises a first ring face and a second ring face opposite to the first ring face. A plurality of field emission electron source is formed by cutting off the plurality of conductive ring, the insulating layer, and the linear carbon nanotube structure, wherein each field emission electron source comprises at least one conductive ring, and a ring face of the conductive ring, end surface of the insulating layer, and end surface of the linear carbon nanotube structure are coplanar.

Abstract: A field emission electron source array includes a number of field emission electron sources aligned side by side. Each field emission electron source includes a linear carbon nanotube structure, an insulating layer and a conductive ring. The linear carbon nanotube structure has a first end and a second end. The insulating layer is coated on an outer surface of the linear carbon nanotube structure. The first conductive ring includes a first ring face and a second ring face, and the first ring face is coplanar with an end surface of the first end of the linear carbon nanotube structure.

Abstract: A method for making field emission electron source array includes following steps. An insulating layer is coated on outer surface of a linear carbon nanotube structure. A field emission electron source preform is formed by locating a plurality of conductive rings on outer surface of the insulating layer, wherein the plurality of conductive rings is space from each other, and each conductive ring comprises a first ring face and a second ring face opposite to the first ring face. A field emission electron source array preform is formed by aligning a plurality of field emission electron source performs side by side. The field emission electron source array preform is severed to form a plurality of field emission electron arrays by cutting the plurality of conductive rings.

Abstract: A system employing vector signal generator (VSG) and vector signal analyzer (VSA) modules or cards that are configured to test multiple devices under test simultaneously. Each VSG is configured to generate multiple RF test signals and send them to multiple devices under test simultaneously. Similarly, each VSA is configured with multiple signal receiving modules connected to a single controller or memory. Each signal receiving module receives an RF signal from a device under test, converts it to a baseband digital signal, and transmits this digital signal to the VSA's memory. A single RF testing system can employ multiple such VSGs and VSAs, each capable of evaluating multiple devices under test. Each VSG/VSA can further be tuned for operation in discrete or defined frequency bands, which are narrower than those for conventional RF testers, and which can correspond to various wireless standards.

Abstract: A system for parallel radio frequency (RF) testing. The system includes a plurality of signal generators, a plurality of signal analyzers, a data bus connected to the plurality of signal generators, and a controller. The controller has a connection to the data bus so as to be in electronic communication with the plurality of signal generators, and has a plurality of point to point links to respective ones of the signal analyzers so as to be in electronic communication with the plurality of signal analyzers.

Abstract: Multi-winding magnetic structures and methods of making multi-winding magnetic structures are disclosed. A multi-winding magnetic structure includes a plurality of windings (512A, 512B; 612A, 612B, 612C; 712A, 712B; 912A, 912B, 912C; 1012A, 1012B; 1112A, 1112B; 1212A, 1212B; 1412; 1512A, 1512B) and a core (402; 502; 602; 702; 902; 1202; 1402; 1502) formed of a magnetic material. The core includes a core top (408; 508; 608; 708; 908; 1208; 1408; 1508), a core bottom (410; 510; 610; 710; 910; 1210; 1410; 1510) and a plurality of columns (404A, 404B, 404C; 504A, 504B; 604A, 604B, 604C; 704A, 704B; 904A, 90413, 904C; 1204; 1404; 1504). The core top has an exterior edge (1522) defining the shape of the core top and a central section (1516) having a substantially constant thickness. The core bottom which is beneath the core top has an exterior edge (1526) defining the shape of the core bottom and a central section (1518) having a substantially constant thickness.

Abstract: The present invention relates to aralkyl piperidine derivatives, compositions containing the same, and their uses in the preparation of antalgic or ataractic medicament. The said derivatives are a free base of the compound represented by the following formula or a salt thereof. The pharmacological experiments show that they display favorable antalgic, ataractic activity and low side effects.

Abstract: A method for establishing a vacuum in a container includes the following steps. The container having an exhaust through hole defined therein is provided. A sealing cover including a connecting material located on the periphery of the sealing cover is provided. The sealing cover is spaced from the exhaust through hole for form at least gaps between the sealing cover and the exhaust through hole. A vacuum is established in the container. The connecting material is heated. The sealing cover covers the exhaust through hole and the connecting material is cooled. After that the container is packaged.

Abstract: Multi-winding magnetic structures and methods of making multi-winding magnetic structures are disclosed. In one embodiment, a multi-winding magnetic structure includes a core constructed of a magnetic material and a plurality of windings. The core includes a core top, a core bottom, and a plurality of columns. The core top has an exterior edge defining a shape of the core top. A central section of the core top has a substantially constant thickness that defines a thickness of the core top. The core bottom is beneath the core top and has an exterior edge defining a shape of the core bottom. A central section of the core bottom has a substantially constant thickness that defines a thickness of the core bottom. The thickness of one of the core bottom and the core top decreases from an edge of its central section to its exterior edge. The plurality of columns extends from the core bottom to the core top and the plurality of windings are wound around the columns.

Abstract: The use of aryl piperazines of formula (I) in manufacturing a medicament for treating acute pain, neuropathic pain or receptive nociceptive pain in mammals including human beings is disclosed.

Abstract: An ion source using a field emission device is provided. The field emission device includes an insulative substrate, an electron pulling electrode, a secondary electron emission layer, a first dielectric layer, a cathode electrode, and an electron emission layer. The electron pulling electrode is located on a surface of the insulative substrate. The secondary electron emission layer is located on a surface of the electron pulling electrode. The cathode electrode is located apart from the electron pulling electrode by the first dielectric layer. The cathode electrode has a surface oriented to the electron pulling electrode and defines a first opening as an electron output portion. The electron emission layer is located on the surface of the cathode electrode and oriented to the electron pulling electrode.