Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: An apparatus can include a pressure vessel that defines an interior region that can contain a liquid and/or a gas. A piston is movably disposed within the interior region of the pressure vessel. A divider is fixedly disposed within the interior region of the pressure vessel and divides the interior region into a first interior region on a first side of the divider and a second interior region on a second, opposite side of the divider. The piston is movable between a first position in which fluid having a first pressure is disposed within the first interior region and the first interior region has a volume less than a volume of the second interior region, and a second position in which fluid having a second pressure is disposed within the second interior region and the second interior region has a volume less than a volume of the first interior region.

Abstract: Systems, devices and methods for the compression, expansion, and/or storage of a gas are described herein. An apparatus suitable for use in a compressed gas-based energy storage and recovery system includes a pneumatic cylinder having a working piston disposed therein for reciprocating movement in the pneumatic cylinder, a hydraulic actuator coupled to the working piston, and a hydraulic controller fluidically coupleable to the hydraulic actuator. The apparatus is fluidically coupleable to a compressed gas storage chamber which includes a first storage chamber fluidically coupleable to the pneumatic chamber, and a second storage chamber is fluidically coupleable to the first storage chamber. The first storage chamber is disposed at a first elevation and is configured to contain a liquid and a gas. The second storage chamber is disposed at a second elevation greater than the first elevation, and is configured to contain a volume of liquid.

Abstract: Systems and methods are described herein to operate an air compression and/or expansion system in its most efficient regime, at a desired efficiency, and/or achieve a desired pressure ratio independent of discharge temperature, with little to no impact on thermal efficiency. For example, systems and methods are provided for controlling and operating hydraulic pumps/motors used within a hydraulically actuated device/system, such as, for example, a gas compression and/or expansion energy system, in its most efficient regime, continuously, substantially continuously, intermittently, or varied throughout an operating cycle or stroke of the system to achieve any desired pressure and temperature profile. Such systems and methods can achieve any desired pressure ratio independent of input or discharge temperature, and can also achieve any desired discharge temperature independent of pressure ratio, without altering any of the structural components of the device or system.

Abstract: Systems, methods and devices for optimizing heat transfer within a device or system used to compress and/or expand a gas, such as air, are described herein. In some embodiments, a compressed air device and/or system can include an actuator such as a hydraulic actuator that can be used to compress a gas within a pressure vessel. An actuator can be actuated to move a liquid into a pressure vessel such that the liquid compresses gas within the pressure vessel. In such a compressor/expander device or system, during the compression and/or expansion process, heat can be transferred to the liquid used to compress the air. The compressor/expander device or system can include a liquid purge system that can be used to remove at least a portion of the liquid to which the heat energy has been transferred such that the liquid can be cooled and then recycled within the system.

Abstract: Systems, methods and devices for optimizing bi-directional piston movement within a device or system used to compress and/or expand a gas, such as air, are described herein. In some embodiments, a compressed air device and/or system can include a first pneumatic cylinder, a second pneumatic cylinder, a hydraulic actuator, and a hydraulic controller. The first pneumatic cylinder has a first working piston disposed therein for reciprocating movement in the first pneumatic cylinder and the hydraulic actuator is coupled to the first working piston. The second pneumatic cylinder has a second working piston disposed therein for reciprocating movement in the second pneumatic cylinder. The hydraulic controller is fluidically coupleable to the hydraulic actuator and is operable in a compression mode.

Abstract: Systems and methods for efficiently operating a hydraulically actuated device/system are described herein. For example, systems and methods for efficiently operating a gas compression and expansion energy storage system are disclosed herein. Systems and methods are provided for controlling and operating the hydraulic actuators used within a hydraulically actuated device/system, such as, for example, a gas compression and/or expansion energy system, within a desired efficiency range of the hydraulic pump(s)/motor(s) used to supply or receive pressurized hydraulic fluid to or from the hydraulic actuators. In such a system, a variety of different operating regimes can be used depending on the desired output gas pressure and the desired stored pressure of the compressed gas. Hydraulic cylinders used to drive working pistons within the system can be selectively actuated to achieve varying force outputs to incrementally increase the gas pressure within the system for a given cycle.

Abstract: An apparatus can include a piston movably disposed within a pressure vessel and defines a first interior region and a second interior region. The piston has a first position in which the first interior contains a gas having a first pressure and has a volume greater than the second interior region, and a second position in which the second interior region contains a gas having a second pressure and has a volume greater than the first interior region. A seal member is attached to the piston and to the pressure vessel. The seal member has a first configuration in which at least a portion of the seal member is disposed at a first position when the piston is in its first position, and a second configuration in which the portion of the seal member is disposed at a second position when the piston is in its second position.

Abstract: Systems and methods for efficiently operating a hydraulically actuated device/system are described herein. For example, systems and methods for efficiently operating a gas compression and expansion energy storage system are disclosed herein. Systems and methods are provided for controlling and operating the hydraulic actuators used within a hydraulically actuated device/system, such as, for example, a gas compression and/or expansion energy system, within a desired efficiency range of the hydraulic pump(s)/motor(s) used to supply or receive pressurized hydraulic fluid to or from the hydraulic actuators. In such a system, a variety of different operating regimes can be used depending on the desired output gas pressure and the desired stored pressure of the compressed gas. Hydraulic cylinders used to drive working pistons within the system can be selectively actuated to achieve varying force outputs to incrementally increase the gas pressure within the system for a given cycle.

Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: Systems, methods and devices for optimizing heat transfer within a device or system used to compress and/or expand a gas, such as air, are described herein. For example, systems, methods and devices for optimizing the heat transfer within an air compression and expansion energy storage system are described herein. A compressor and/or expander device can include one or more of various embodiments of a heat transfer element that can be disposed within an interior of a cylinder or pressure vessel used in the compression and/or expansion of a gas, such as air. Such devices can include hydraulic and/or pneumatic actuators to move a fluid (e.g., liquid or gas) within the cylinder or pressure vessel. The heat transfer element can be used to remove heat energy generated during a compression and/or expansion process.

Abstract: Systems and methods for efficiently operating a hydraulically actuated device/system are described herein. For example, systems and methods for efficiently operating a gas compression and expansion energy storage system are disclosed herein. Systems and methods are provided for controlling and operating the hydraulic actuators used within a hydraulically actuated device/system, such as, for example, a gas compression and/or expansion energy system, within a desired efficiency range of the hydraulic pump(s)/motor(s) used to supply or receive pressurized hydraulic fluid to or from the hydraulic actuators. In such a system, a variety of different operating regimes can be used depending on the desired output gas pressure and the desired stored pressure of the compressed gas. Hydraulic cylinders used to drive working pistons within the system can be selectively actuated to achieve varying force outputs to incrementally increase the gas pressure within the system for a given cycle.

Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: Systems and methods for operating a hydraulically actuated device/system are described herein. For example, systems and methods for the compression and/or expansion of gas can include at least one pressure vessel defining an interior region for retaining at least one of a volume of liquid or a volume of gas and an actuator coupled to and in fluid communication with the pressure vessel. The actuator can have a first mode of operation in which a volume of liquid disposed within the pressure vessel is moved to compress and move gas out of the pressure vessel. The actuator can have a second mode of operation in which a volume of liquid disposed within the pressure vessel is moved by an expanding gas entering the pressure vessel. The system can further include a heat transfer device configured to transfer heat to or from the at least one of a volume of liquid or a volume of gas retained by the pressure vessel.

Abstract: A telephone system supports communication with user devices over both a cellular radio network as well as over an Internet Protocol (IP) network, and enables roaming and active call handoff between cellular and IP domains. Approaches to detecting presence of a user near a suitable IP network are used in controlling transitions between the domains, for example, enabling automatic transitions between domains, and delivery of calls to a mobile user to data network devices in the vicinity of the user.

Abstract: Location information for a client is determined prior to establishing a communication tunnel over which the client accesses network based services. The location information is passed over the communication tunnel, and the network based services are provided based on the location information.

Abstract: Methods and apparatus for detecting a change in demand for server resources across a load-bearing system having one or more content servers hosting identical content, the load-bearing system being connected to a network of content servers; and automatically modifying the number of content servers on the load-bearing system in response to the change in demand.

Abstract: Methods and apparatus for detecting a change in demand for server resources across a load-bearing system having one or more content servers hosting identical content, the load-bearing system being connected to a network of content servers; and automatically modifying the number of content servers on the load-bearing system in response to the change in demand.

Abstract: Location data associating data network access devices with corresponding physical locations is maintained, a voice service from a mobile device served by a data network access device is accessed, and location data during the voice service is accessed to determine if the data network access device has a corresponding physical location in the location data.