Abstract: Systems and methods for automatically provisioning a service instance in a cloud computing system are presented. In an example embodiment, a message is retrieved by one of multiple provisioner nodes from a message queue shared by the provisioner nodes, the message including a service request to provision a service instance on the computing infrastructure. The provisioner node that retrieved the message may determine whether a resource of the computing infrastructure capable of hosting the service instance is available, and if not, may cause a creating on the computing infrastructure of a resource capable of hosting the service instance. The provisioner node may also cause deployment and configuration of software for providing the service instance on the resource.

Abstract: Systems and methods for automatically provisioning a service instance in a cloud computing system are presented. In an example embodiment, a message is retrieved by one of multiple provisioner nodes from a message queue shared by the provisioner nodes, the message including a service request to provision a service instance on the computing infrastructure. The provisioner node that retrieved the message may determine whether a resource of the computing infrastructure capable of hosting the service instance is available, and if not, may cause a creating on the computing infrastructure of a resource capable of hosting the service instance. The provisioner node may also cause deployment and configuration of software for providing the service instance on the resource.

Abstract: A sampling device includes a barrel having a downhole end, an exterior surface, an interior surface defining a hollow interior, and an open end at the downhole end of the hollow interior. A fluid entrance penetrates the exterior surface. A fluid path having an outlet port is fluidly coupled to the fluid entrance. The device is driven into a subsurface so that a soil sample is forced into the hollow interior. While the device is still in the subsurface a fluid sample is collected through the least one fluid entrance and fluid path.

Abstract: A sampling device includes a barrel having a downhole end, an exterior surface, an interior surface defining a hollow interior, and an open end at the downhole end of the hollow interior. A fluid entrance penetrates the exterior surface. A fluid path having an outlet port is fluidly coupled to the fluid entrance. The device is driven into a subsurface so that a soil sample is forced into the hollow interior. While the device is still in the subsurface a fluid sample is collected through the least one fluid entrance and fluid path.

Abstract: A subsurface barrier wall having a number of interconnected columns is disclosed. The columns are driven into the subsurface, one next to the other in interlocking fashion, with a percussive drive hammer. A sonic drilling tool is driven ahead of the columns. The columns include interconnecting elements which slidably couple adjacent columns together as a column is being driven into the subsurface. The barrier wall may be used to divert, contain, or remediate the migration of subsurface contaminants.

Abstract: A sampling device includes a barrel having a downhole end, an exterior surface, an interior surface defining a hollow interior, and an open end at the downhole end of the hollow interior. A fluid entrance penetrates the exterior surface. A fluid path having an outlet port is fluidly coupled to the fluid entrance. The device is driven into a subsurface so that a soil sample is forced into the hollow interior. While the device is still in the subsurface a fluid sample is collected through the least one fluid entrance and fluid path.

Abstract: In combination with resonant sonic earth drilling components, and for particular use in retrieving a core sample in a core barrel seated against an internal shoulder in a sonically driven drill bit, a resilient axial loading device not only urges the bottom of the core barrel into continuous contact with the seat but also cushions the core barrel from the sonic energy in the drill bit, thereby minimizing damage to the core sample.

Abstract: A drill string is advanced into the ground by inducing vibrations in the drill string at a resonant frequency. The drill string has an opening at a downhole end leading to a hollow interior. As drilling progresses, a core enters the hollow interior. A casing is driven around the drill string to seal the borehole. Sonic advancing of the drill string minimizes waste materials and can be operated without a circulating fluid.

Abstract: A sampling device includes a barrel having a downhole end, an exterior surface, an interior surface defining a hollow interior, and an open end at the downhole end of the hollow interior. A fluid entrance penetrates the exterior surface. A fluid path having an outlet port is fluidly coupled to the fluid entrance. The device is driven into a subsurface so that a soil sample is forced into the hollow interior. While the device is still in the subsurface a fluid sample is collected through the least one fluid entrance and fluid path.

Abstract: High accuracy is achieved by employing, in conventional DAC architectures, very accurate current sources. To create these high-accuracy current sources, the outputs of several smaller, less accurate, nominally equal current sources are summed. A procedure is taught for selecting the number of current sources to achieve an arbitrary degree of accuracy with a desired level of confidence. Assuming the current sources are taken from a population whose output currents deviate from a design value according to a normal distribution, the minimum number of constituent current sources, n, required to provide an accurate total current is given by the formula n=(Z.sigma./E).sup.2, where Z is a number which corresponds to the probability that the output will fall within an error band E (i.e., a predetermined accuracy level) with a predetermined level of confidence, .sigma. is the standard deviation of the population.