Abstract: A method for controlling a BLDC motor includes controlling the rotational speed or position of the BLDC motor based on a position of the rotor of the motor. The BLDC motor is driven by a three-phase inverter. A PWM signal is generated for three PWM phases, each including a pair of complementary signals with dead-time and having a duty cycle based on the current position of the rotor. The complementary signals are supplied to a respective high side and low side switch of each of three arms of the three-phase inverter, and a zero-crossing time measurement is performed on each of the back electromotive forces. Corresponding signals are obtained indicating the zero-crossing times. Trigger signals are generated, and the occurrence of a time interval corresponding to the dead time in the respective PWM phase is identified. The zero-crossing time measurement is performed during the occurrence of the dead-time.

Abstract: Apparatus, methods, and a computer program for determining a refraction of an eye are disclosed. An apparatus for determining an objective refraction of an eye is disclosed where the apparatus includes an optical element configured to compensate an aberration of the eye.

Abstract: An apparatus can include a partial superblock memory management component. The partial superblock memory management component can identify bad blocks in respective planes of a block of non-volatile memory cells. The partial superblock memory management component can determine that a plane of the respective planes includes at least good block in at least one different block of non-volatile memory cells. The partial superblock memory management component can perform an operation to reallocate the at least one good block in the plane to the at least one bad block in the plane to form blocks of non-volatile memory cells having a quantity of bad blocks that satisfies a bad block threshold.

Abstract: A variety of applications can include apparatus and/or methods of operating the apparatus in which storage in the memory device is managed. An allocation can include conducting a garbage collection procedure to free up one or more blocks. In various embodiments, execution of a garbage collection procedure can be based on operation of two tables with respect to a logical to physical mapping table split into logical to physical mapping table regions saved in the memory device. The first table can maintain counts of valid pages in blocks for a logical to physical mapping table region. The second table can include bits to identify logical to physical mapping table regions involved in the garbage collection procedure based on the entries in the first table. Search of the second table can determine logical to physical mapping table regions involved in the garbage collection. Additional apparatus, systems, and methods are disclosed.

Abstract: A turbomachine, a computing system for a turbomachine, and a method for overspeed protection are provided. The turbomachine includes a first rotor assembly interdigitated with a second rotor assembly together operably coupled to a gear assembly. A plurality of sensors is configured to receive rotor state data indicative of one or more of a speed, geometric dimension, or capacitance, or change thereof, or rate of change thereof, relative to the first rotor assembly or the second rotor assembly. A controller executes operations including receiving rotor state data from the plurality of sensors; comparing rotor state data to one or more rotor state limits; and contacting one or more of the first rotor assembly or the second rotor assembly to a contact surface adjacent to the respective first rotor assembly or the second rotor assembly if the rotor state data exceeds the rotor state limit.

Abstract: In one approach, a computer storage device has one or more pivot tables and corresponding bit maps stored in volatile memory. The storage device has non-volatile storage media that stores data for a host device. The pivot tables and bit maps are used to determine physical addresses of the non-volatile storage media for logical addresses received in commands from the host device that are determined to be within a sequential address range (e.g., LBAs that are part of a prior sequential write operation by the host device). When a command is received by the storage device that includes a logical address within the sequential address range, then one of the pivot tables and its corresponding bit map are used to determine the physical address of the non-volatile storage media that corresponds to the logical address.

Abstract: Systems and methods are disclosed, including, in a storage system comprising control circuitry and a memory array having multiple groups of memory cells, storing a first physical-to-logical (P2L) data structure for a first physical area of a first group of memory cells in a second physical area of the first group of memory cells, such as when resuming operation from a low-power state, including an asynchronous power loss (APL). The first group of memory cells can include a super block of memory cells. A second P2L data structure for the second physical area of the first group of memory cells can be stored, such as in a metadata area of the second physical area and an address of the first P2L data structure can be stored in the second P2L data structure.

Abstract: Devices and techniques for controlling NAND operation latency are described herein. A controlled can receive a write request. The controller can then calculate a number of garbage collection operations to perform on a physical block that is closed. Here, the calculation includes adding a logical-to-physical (L2P) region search ratio to a cadence calculation for garbage collection. Garbage collection operations can be performed on the physical block in accordance with the calculated number of garbage collection operations to perform. Then, the controller can perform the write request in response to completing the calculated number of garbage collection operations.

Abstract: A method of servicing a gas turbine engine, the method including preparing the gas turbine engine for service; installing a shaft protection cover to an aft end of a fan shaft of the gas turbine engine; installing an oil collector drum at least partially around a gearbox of the gas turbine engine; and removing at least a portion of the gearbox from the gas turbine engine.

Abstract: A variety of applications can include systems and methods that utilize a hybrid logical to physical (L2P) caching scheme. A L2P cache and a L2P changelog in a storage device can be controlled for use in write and read operations of a memory system. A page pointer table in the L2P cache can be accessed, for performance of a write operation in the memory system, to obtain a specific physical address mapped to a specified logical block address from a host, where the access is based on the page pointer table loaded into the L2P cache from the L2P changelog. The L2P cache area can be progressively configured with the most frequently accessed page pointer tables in the L2P changelog in the latest host accesses.

Abstract: Disclosed in some examples are improvements to data placement architectures in NAND that provide additional data protection through an improved NAND data placement schema that allows for recovery from certain failure scenarios. The present disclosure stripes data diagonally across page lines and planes to enhance the data protection. Parity bits are stored in SLC blocks for extra protection until the block is finished writing and then the parity bits may be deleted.

Abstract: A turbomachine having an engine centerline and a first rotor. The first rotor having a first annular drum and being connected to a first plurality of blades. At least one blade of the first plurality of blades having a blade root, a blade tip, a first arm, a second arm and a first seal. The first arm extending from the blade root and having a radial retention hook. The second arm extending from the blade tip.

Abstract: Methods, systems, and devices for integrating a pivot table in a logical-to-physical mapping of a memory system are described. The memory system may receive a read command and read a first entry of a first subset of mapping and a second entry of a second subset of mapping. The second entry may include at least a portion of a pivot table associated with physical addresses of a non-volatile memory device. The memory system may retrieve data from a physical address identified in the pivot table, rather than access a different portion of the logical-to-physical mapping. The memory system may transmit, to a host system, the data retrieved from the physical address identified in the pivot table.

Abstract: Disclosed in some examples are improvements to data placement architectures in NAND that provide additional data protection through an improved NAND data placement schema that allows for recovery from certain failure scenarios. The present disclosure stripes data diagonally across page lines and planes to enhance the data protection. Parity bits are stored in SLC blocks for extra protection until the block is finished writing and then the parity bits may be deleted.

Abstract: Methods, systems, and devices for memory operations are described. A memory system may write data to sequential physical addresses of the memory system based on receiving multiple write commands, where the sequential physical addresses may be associated with sequential logical addresses. Based on writing the data, the memory system may receive a read command for data stored in the memory system, where the read command may include a logical address. The memory system may determine a physical address of the memory system where the data is stored based on the received logical address, a last logical address written at the memory system, and a sequence number group associated with the last logical address. Based on determining the physical address, the memory system may read the data stored at the physical address.

Abstract: A blade for a turbomachine includes a blade root portion for securing the blade to a rotatable annular outer drum rotor. The blade root portion includes one or more radial retention features for radially retaining each of the blade root portions within the rotatable annular outer drum rotor. Further, at least one of the radial retention feature(s) includes at least one sealing member integrated therewith.

Abstract: An apparatus can include a partial superblock memory management component. The partial superblock memory management component can identify bad blocks in respective planes of a block of non-volatile memory cells. The partial superblock memory management component can determine that a plane of the respective planes includes at least good block in at least one different block of non-volatile memory cells. The partial superblock memory management component can perform an operation to reallocate the at least one good block in the plane to the at least one bad block in the plane to form blocks of non-volatile memory cells having a quantity of bad blocks that satisfies a bad block threshold.

Abstract: A variety of applications can include apparatus and/or methods of operating the apparatus in which storage in the memory device is managed. An allocation can include conducting a garbage collection procedure to free up one or more blocks. In various embodiments, execution of a garbage collection procedure can be based on operation of two tables with respect to a logical to physical mapping table split into logical to physical mapping table regions saved in the memory device. The first table can maintain counts of valid pages in blocks for a logical to physical mapping table region. The second table can include bits to identify logical to physical mapping table regions involved in the garbage collection procedure based on the entries in the first table. Search of the second table can determine logical to physical mapping table regions involved in the garbage collection. Additional apparatus, systems, and methods are disclosed.

Abstract: Methods, systems, and devices for setting switching for single-level cells (SLCs) are described. A memory system may receive an access command from a host. The access command may correspond to an SLC block or to a multiple-level cell block. If the access command corresponds to an SLC block, the memory system may modify the access command to include one or more bits indicating a setting to use for performing the access operation corresponding to the access command. The setting may define one or more operating parameters for performing the access operation. The memory system may use bits to indicate the setting that are used to indicate a page address for multiple-level cell blocks. The memory system may issue the access command to a memory device, which may perform the access operation using the setting indicated in the one or more bits included by the memory system.

Abstract: Disclosed in some examples are improvements to data placement architectures in NAND that provide additional data protection through an improved NAND data placement schema that allows for recovery from certain failure scenarios. The present disclosure stripes data diagonally across page lines and planes to enhance the data protection. Parity bits are stored in SLC blocks for extra protection until the block is finished writing and then the parity bits may be deleted.