Abstract: Techniques are described for providing a storage service that stores information about large numbers of transactions in a persistent manner, such as with a high degree of reliability, availability and scalability based at least in part on use of a distributed computing and storage system. In some situations, the transaction information storage service stores various information about transactions that each include at least one monetary payment (e.g., a micro-payment) between financial accounts of two or more of numerous users having accounts with one or more entities. The transaction information storage service may be provided by or otherwise affiliated with a merchant, and customers of the merchant may purchase usage of the storage service for programs executed by or otherwise affiliated with the customers, with the storage service available to remote executing programs via a defined API of the storage service, such as a Web services-based API.

Abstract: In one embodiment, a method may comprise receiving a query to search for one or more entities of the data center, the query including one or more query tokens. The method may then identify one or more entity-type nodes corresponding to the query, and rank the entity-type nodes based on a score determined for each of the identified entity-type nodes. For at least a portion of the ranked entity-type nodes, the method may generate a structured query associated with each of the entity-type nodes based at least in part of one or more activity-type nodes connected to each of the entity-type nodes. Then, the method may retrieve, based on the structured queries, results from one or more databases.

Abstract: Identifying state inconsistency in edge-based software defined networks is disclosed. A verification server may receive controller network configuration data from a controller of an edge-based software defined network (SDN) and end-host network configuration data from at least one end-host of the SDN. The verification server may parse the controller network configuration data into a network state representation and the end-host network configuration data into the network state representation. The network state representation of the controller network configuration data and the end-host network configuration data may be compared to identify state inconsistency in the SDN. Responsive to identifying the state inconsistency, an alert and/or a report may be generated and transmitted to an administrator user interface.

Abstract: Techniques are described for providing a storage service that stores information about large numbers of transactions in a persistent manner, such as with a high degree of reliability, availability and scalability based at least in part on use of a distributed computing and storage system. In some situations, the transaction information storage service stores various information about transactions that each include at least one monetary payment (e.g., a micro-payment) between financial accounts of two or more of numerous users having accounts with one or more entities. The transaction information storage service may be provided by or otherwise affiliated with a merchant, and customers of the merchant may purchase usage of the storage service for programs executed by or otherwise affiliated with the customers, with the storage service available to remote executing programs via a defined API of the storage service, such as a Web services-based API.

Abstract: In particular embodiments, a system for managing a virtualization environment includes host machines, each of the host machines including a hypervisor, user virtual machines (UVMs) and a virtual machine controller. The virtualization environment also includes virtual disks comprising a plurality of storage devices, and being accessible by the virtual machine controllers. The virtual machine controllers conduct I/O transactions with the virtual disks. The system stores an entity-relationship graph representing elements in the virtualization environment. Each of the elements is represented by an entity-type node in the entity-relationship graph, and relationships between the elements are represented by edges between the nodes.

Abstract: In one embodiment, a computing device accesses an entity database storing information about entities in a virtualization environment. Each of the entities is associated with a single entity type and a shard. The shard further corresponds to the single entity type. The computing device determines an entity trail for the single shard, based on a modification history for one or more of the entities associated with the shard. The entity trail is divided into a plurality of time segments. The computing device receives an update from a client device indicating an update to an entity that is associated with the shard, and a client timestamp. The computing device selects a time segment corresponding to the client timestamp, and updates that portion of the entity trail with the client update.

Abstract: In particular embodiments, a system for managing a virtualization environment includes host machines, each of the host machines including a hypervisor, user virtual machines (UVMs) and a virtual machine controller. The virtualization environment also includes virtual disks comprising a plurality of storage devices, and being accessible by the virtual machine controllers. The virtual machine controllers conduct I/O transactions with the virtual disks. The system stores an entity-relationship graph representing elements in the virtualization environment. Each of the elements is represented by an entity-type node in the entity-relationship graph, and relationships between the elements are represented by edges between the nodes.

Abstract: A bipolar junction transistor (BJT) may be used to generate a supply voltage for operating a controller, such as a lighting controller for a LED-based light bulb. A base of the BJT may receive current generated from the supply voltage to control operation of the BJT. Although the base of the BJT would be at a lower voltage than the emitter, a base drive circuit may be coupled between the emitter and the base of the BJT to increase the voltage. As one example, the base drive circuit may be a charge pump. In another example, the BJT may function as its own charge pump. In yet another example, a positive and a negative base current of the BJT may be independently controlled to regulate an output supply voltage VDD from the BJT.

Abstract: An LED lighting device includes an auxiliary power supply that supplies power to a control circuit of the LED lighting device that receives an input from a terminal of a light-emitting diode (LED) string of the lighting device that has a substantially lower voltage than the line voltage to which the lighting device is connected. The terminal may be within the LED string, or may be an end of the string. A linear regulator may be operated from the voltage drop across a number of the LEDs in the string so that the energy wasted by the auxiliary power supply is minimized. In other designs, the auxiliary power supply may be intermittently connected in series with the LED string only when needed. The intermittent connection can be used to forward bias a portion of the LED string when the voltage supplied to the LED string is low, increasing overall brightness.

Abstract: Identifying state inconsistency in edge-based software defined networks is disclosed. A verification server may receive controller network configuration data from a controller of an edge-based software defined network (SDN) and end-host network configuration data from at least one end-host of the SDN. The verification server may parse the controller network configuration data into a network state representation and the end-host network configuration data into the network state representation. The network state representation of the controller network configuration data and the end-host network configuration data may be compared to identify state inconsistency in the SDN. Responsive to identifying the state inconsistency, an alert and/or a report may be generated and transmitted to an administrator user interface.

Abstract: In some aspects, a local oscillator includes a voltage controlled oscillator, a multi-stage frequency divider including first and second stages, and a duty-cycle converter. An output node of the voltage controlled oscillator is coupled to an input node of the first stage. An output node of the first stage is coupled to an input node of the second stage. The first stage is configured to output a first signal from one of a first plurality of signal paths, each configured to provide a signal having a distinct frequency. The second stage is configured to output a second signal from one of a second plurality of signal paths, each configured to provide a signal having a distinct frequency. An output node of the multi-stage frequency divider is coupled to an input node of the duty-cycle converter.

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. The controller may operate the power stage by monitoring a start and end of a reverse recovery time of the BJT. Information regarding the start and end of the reverse recovery time may be used in the control of the power stage to improve efficiency of the power stage.

Abstract: An ultrasound signal processor uses an excitation generator to cause displacement of a tympanic membrane while a series of ultrasound pulses are applied to the tympanic membrane. Phase differences between a transmitted signal and received signal are examined to determine the movement of the tympanic membrane in response to the applied excitation. An examination of the phase response of the tympanic membrane provides a determination as to whether the fluid type behind the tympanic membrane is one of: no fluid, serum fluid, or purulent fluid.

Abstract: Nucleic acid sequence encoding Allium fistulosum leaf agglutinin (AFAL) is disclosed. The invention provides Allium fistulosum leaf agglutinin (AFAL) recombinant protein, its encoding nucleotides, primers and the process of preparation thereof, said recombinant protein is useful for insect control and haemagglutination activity. AFAL is found more toxic to sap sucking insect pest Aphis gossypii (cotton aphid) and Bemisia tabaci (whiteflies) as compared to known Allium sativum leaf agglutinin. AFAL can be used in the development of transgenic plants for resistance against sap sucking and chewing pests.

Abstract: An electronic system and method include a controller to operate in a start-up mode to accelerate driving a load to an operating voltage and then operates in a post-start-up mode. A start-up condition occurs when the controller detects that a load voltage is below a predetermined voltage threshold level. The predetermined voltage threshold level is set so that the controller will boost the voltage to an operating value of a load voltage at a faster rate than during normal, steady-state operation. The controller causes a switching power converter to provide charge to the load at a rate in accordance with a start-up mode until reaching an energy-indicating threshold. When the energy-indicating threshold has been reached, the controller causes the switching power converter to (i) decrease the amount of charge provided to the load relative to the charge provided during the start-up mode and (ii) operate in a distinct post-start-up-mode.

Abstract: A turn-off transition time period, also referred to as a reverse recovery time period, may be compensated for by a controller of a power stage including a bipolar junction transistor (BJT). The reverse recovery time period may be measured in one switching cycle and a subsequent switching cycle may include compensations based on the measured reverse recovery time period. That is the switching on and off of the BJT may be compensated to obtain a desired average output current to a load. When the reverse recovery time period is known, an error in the peak current obtained due to the reverse recovery time period may be calculated. The calculated error may be used to offset the target peak current for controlling the switching of the BJT to begin a turn-off transition of the BJT earlier in a switching cycle and thus reduce error in peak current at the BJT.

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. A resistor may be coupled to the BJT through a switch at the emitter of the BJT. The switch may regulate operation of the BJT by allowing current flow to ground through the resistor. The controller may perform measurements of the resistor to allow higher accuracy determinations of the current through the BJT and thus improve regulation of current to the LED load.

Abstract: An example embodiment discloses a flip-flop including a first inverter configured to invert first data, first and second transistors connected to each other in series and configured to receive the inverted first data and a first clock, respectively, a third transistor and a first gate configured to perform a logic operation on the first data and the first clock, the third transistor configured to receive an output of the logic operation. The second transistor and the third transistor are connected to a first node.

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as for LED-based light bulbs. The BJT may be switched on and off from a controller coupled to two terminals of the BJT. Through the two terminals, the control IC may dynamically adjust a reverse recovery time period of the BJT. The reverse recovery time period may be adjusted by changing an amount of base charge that accumulates on the BJT. Additional, the reverse recovery may be controlled through the use of a reverse base current source applied to the BJT after beginning switching off the BJT.

Abstract: Network disconnections are automatically detected between a client application and a server When a disconnection is detected by either the client or server, a determination is made as to whether the disconnection is a temporary disconnection or a longer-lasting disconnection. While disconnected, attempts are made to automatically reconnect the client and server. During the disconnected period, a subset of communication functions remain operable. When the connection is restored, presence/availability information is automatically delivered to the client.