Abstract:
A virtualization infrastructure that allows multiple guest partitions to run within a host hardware partition. The host system is divided into distinct logical or virtual partitions and special infrastructure partitions are implemented to control resource management and to control physical I/O device drivers that are, in turn, used by operating systems in other distinct logical or virtual guest partitions. Host hardware resource management runs as a tracking application in a resource management “ultravisor” partition, while host resource management decisions are performed in a higher level command partition based on policies maintained in a separate operations partition. The conventional hypervisor is reduced to a context switching and containment element (monitor) for the respective partitions, while the system resource management functionality is implemented in the ultravisor partition. The ultravisor partition maintains the master in-memory database of the hardware resource allocations and serves a command channel to accept transactional requests for assignment of resources to partitions. It also provides individual read-only views of individual partitions to the associated partition monitors. Host hardware I/O management is implemented in special redundant I/O partitions. Operating systems in other logical or virtual partitions communicate with the I/O partitions via memory channels established by the ultravisor partition. The guest operating systems in the respective logical or virtual partitions are modified to access monitors that implement a system call interface through which the ultravisor, I/O, and any other special infrastructure partitions may initiate communications with each other and with the respective guest partitions. The guest operating systems are modified so that they do not attempt to use the “broken” instructions in the x86 system that complete virtualization systems must resolve by inserting traps.
Abstract:
A device comprising an array of free metal ribbons that are coupled to a substrate through ceramic support structures is disclosed. The device is preferably an optical MEM device, wherein a first set of free metal ribbons are configured to move relative to a second set of alternating free metal ribbons for modulating an incident light source. An optical MEM system in accordance with the invention includes a light source and suitable optics for transmitting light to and from the array of free metal ribbons. The optical MEM device exhibits reduced surface charging and has applications in optical communications.
Abstract:
An optical MEM device is fabricated with a patterned device layer formed on a silicon wafer. Preferably, the patterned device layer is patterned with plurality of ribbons and/or access trenches. The central portion of the ribbon is released from the silicon wafer using a selective etch process, wherein a cavity is formed under the central portion of the ribbon, while opposing ribbon ends remain attached to the wafer. The selective etching process preferably utilizes an enchant comprising xenon difluoride. In accordance with further embodiments, the silicon wafer is doped, patterned or otherwise modified to enhance the selectivity of the etching process.
Abstract:
A MEM device in accordance with the invention comprises one or more movable micro-structures which are preferably ribbon structures or cantilever structures. The ribbon structures or cantilever structures are preferably coupled to a substrate structure through one or more support regions comprising a plurality of anchor support features and a plurality of post support features. The MEM device is preferably an optical MEM device with a plurality of movable ribbon structures each being supported by opposing ends through support regions each comprising a plurality of anchor support features and a plurality of post support features. In accordance with the method of the embodiments, the positions of the anchor and post support features, the number of anchor and support features and the spacings between the support features can selected during fabrication of the device to determine an operating condition of the MEM device.
Abstract:
A kit for converting a cross-legged folding cot into a tiered cot, which stilt legs having a longitudinal axis, a top end and a bottom end. A female coupling is positioned at the top end of each of the stilt legs. Each female coupling is offset from the longitudinal axis by between 45 degrees and 65 degrees, and is adapted to receive a leg from a first cross-legged folding cot. With each female coupling holding a leg of a first cross-legged folding cot, the first cot is effectively elevated, such that gear can be stowed or a second cot can be positioned in the space provided beneath the first cot between the stilt legs.
Abstract:
A MEM device in accordance with the invention comprises one or more movable micro-structures which are preferably ribbon structures or cantilever structures. The ribbon structures or cantilever structures are preferably coupled to a substrate structure through one or more support regions comprising a plurality of anchor support features and a plurality of post support features. The MEM device is preferably an optical MEM device with a plurality of movable ribbon structures each being supported by opposing ends through support regions each comprising a plurality of anchor support features and a plurality of post support features. In accordance with the method of the embodiments, the positions of the anchor and post support features, the number of anchor and support features and the spacings between the support features can selected during fabrication of the device to determine an operating condition of the MEM device.
Abstract:
A light modulator includes elongated elements arranged parallel to each other. In a first diffraction mode, the light modulator operates to diffract an incident light into at least two diffraction orders. In a second diffraction mode, the light modulator operates to diffract the incident light into a single diffraction order. Each of the elongated elements comprises a blaze profile, which preferably comprises a reflective stepped profile across a width of each of the elongated elements and which produces an effective blaze at a blaze angle. Alternatively, the blaze profile comprises a reflective surface angled at the blaze angle. Each of selected ones of the elongated elements comprise a first conductive element. The elongated elements produce the first diffraction when a first electrical bias is applied between the first conductive elements and a substrate. A relative height of the blazed portions are adjusted to produce the second diffraction when a second electrical bias is applied between the first conductive elements and the substrate. In an alternative embodiment, each of the elongated elements includes the first conductive element and multiple elongated elements are arranged in groupings, where each of the groupings includes at least three of the elongated elements. When the multiple elongated elements are at a first height, the incident light reflects from the elongated elements. When relative heights of the multiple elongated elements are adjusted by applying individual electrical biases between the first conductive elements and the substrate, the incident light diffracts into the single diffraction order.
Abstract:
A grating light valve with reduced surface charging is disclosed. Surface charging is measured by the propensity an insulating surface to accept and transport a charge. The grating light valve of the instant invention has a plurality of spaced and movable ribbons formed from Si3N4 coupled to a substrate structure formed of SiO2. A portion of the ribbons are moved to alternate between conditions for constructive and destructive interference with an incident light source having a wavelength &lgr; by applying the appropriate switching voltages across the portion of ribbons and the substrate structure. When charging occurs on surfaces of the grating light valve, the switching voltages required to operate the grating light valve are shifted and diminishing the performance of the grating light valve. By drying silicon-based surfaces of the grating light valve and exposing the silicon-based surfaces of the grating light valve to a Nitrogen-rich pacify gas environment, the surfaces of the grating light valve exhibit reduced charging and consistent response to applied bias voltages. In the drying step, residual water or moisture is removed from the surfaces by elevating the temperature of the grating light valve structure in a vacuum environment. Preferably, the drying is carried at temperatures of 250 degrees Celsius or greater and at vacuum pressures of 10−6 Torr or less. After the surface of the grating light valve are dried, the surfaces are exposed to the Nitrogen-rich pacifying gas environment at ambient temperature. Presumably, the Nitrogen-rich pacify gas environment blankets the silicon-based surfaces of the grating light valve with adsorbed, physisorbed, or chemi-adsorbed Nitrogen and thus reduces the propensity of those surfaces to accept water or moisture, which is believed to facilitate the charging. After the surfaces of the grating light valve are treated according to the current invention, charging of the surface remains low and stable even for several days in open air conditions.
Abstract:
When fumigating a bulk particulate commodity stored in a top-vented vertical silo by slowly passing a gas containing a low concentration of a gaseous fumigant through the bulk mass, differences between the temperature, T.sub.g, in the bulk mass and the ambient temperature, T.sub.a, outside the silo cause a "chimney effect" within the silo, and possible unwanted dilution of the fumigant. The chimney effect also occurs in other top-vented storage structures containing particulate commodities. To overcome the chimney effect, the fumigant-containing gas is supplied through a duct to the base of the storage structure at a flow rate Q.sub.f (in m.sup.3 sec.sup.1) determined by the relationship ##EQU1## where g is the acceleration due to gravity (approximately 9.8 m sec .sup.2); P.sub.a is the atmospheric pressure expressed in Pascals; R.sub.a is the gas constant for air (=287 J kg.sup.-1 K.sup.-1); T.sub.a is in K; T.sub.g is also in K; R is a resistance factor (in Pascals sec m.sup.-2) which depends upon the nature of the commodity in the storage structure; and A is the horizontal cross-sectional area of the storage structure, in square meters. This technique can also be used to maintain effective fumigation of a plurality of storage structures in a storage facility, from a single source of gaseous fumigant.