Abstract:
In a cellular system, channels are assigned for new calls using a flexible channel allocation algorithm that is a hybrid of a measurement-based dynamic channel assignment (MBDCA) algorithm and a reuse-distance criterion algorithm, such as a cost-function-based DCA (CFBDCA). In one embodiment, the MBDCA algorithm is implemented at each cell site in the cellular system and generates a list of candidate channels for each new call. The list is transmitted to the mobile switching center (MSC), which implements the CFBDCA algorithm to select a particular channel from the list of candidate channels for the new call.
Abstract:
In a cellular system, channels are assigned for new calls using a cost-function-based dynamic channel assignment (CFBDCA) algorithm. In one embodiment, the CFBDCA algorithm is implemented in the cellular system's mobile switching center (MSC), which maintains a database containing one or more cost tables and a busy channel table. The entries in the cost tables reflect the costs of using a candidate channel in one particular cell of the cellular system, assuming that the channel is already being used in another particular cell. The entries in the busy channel table identify which channels are currently being used in which cells. The CFBDCA algorithm uses the cost tables and the busy channel table to generate cost of reusing the channel (CORC) values. Depending on the implementation, the CFBDCA algorithm of the present invention may or may not be used in conjunction with a measurement-based DCA (MBDCA) algorithm. If so, then the CFBDCA algorithm may be applied to a list of candidate channels generated using the MBDCA algorithm.
Abstract:
A method and controller system are described for automatically tuning a controller of a drilling rig. The controller system includes a controller that determines a moving average of measured values, determines a moving standard deviation of the measured values, defines an outer zone of measured values with the determined moving average and the determined moving standard deviation, defines an inner zone of measured values with the determined moving average and the determined moving standard deviation, monitors the measured values for the occurrence of statistical events with respect to the outer zone and inner zone. Based on the detected statistical event, the controller adjusts the gain of the controller the based on the statistical event being associated with the outer zone or inner zone.
Abstract:
Methods for drilling a wellbore within a subsurface region and drilling assemblies and systems that include and/or utilize the methods are disclosed herein. The methods include receiving a plurality of drilling performance indicator maps, normalizing the plurality of drilling performance indicator maps to generate a plurality of normalized maps, adaptive trending of the plurality of drilling performance indicator maps to generate a plurality of trended maps, summing the plurality of trended maps to generate an objective map, selecting a desired operating regime from the objective map, and adjusting at least one drilling operational parameter of a drilling rig based, at least in part, on the desired operating regime.
Abstract:
Method for analyzing seismic data representing a subsurface region for presence of a hydrocarbon system or a particular play. Seismic attributes are computed, the attributes being selected to relate to the classical elements of a hydrocarbon system, namely reservoir, seal, trap, source, maturation, and migration. Preferably, the attributes are computed along structural fabrics (1) of the subsurface region, and are smoothed over at least tens or hundreds of data voxels. The resulting geologic attributes (2) are used to analyze the data for elements of the hydrocarbon system and/or recognition of specific plays, and for ranking and annotating partitioned regions (3) of the data volume based on size, quality, and confidence in the prospectivity prediction (5). A catalog (8) of hydrocarbon trap configurations may be created and used to identify potential presence of hydrocarbon traps and/or aid in scoring (4) and ranking partitioned regions as hydrocarbon prospects.
Abstract:
An automated method for texture segmentation (11) of geophysical data volumes, where texture is defined by double-window statistics of data values, the statistics being generated by a smaller pattern window moving around within a larger sampling window (12). A measure of “distance” between two locations is selected based on similarity between the double-window statistics from sampling windows centered at the two locations (13). Clustering of locations is then based on distance proximity (14).
Abstract:
The behavior of a monitored condition over time for a reactor or reaction system can be analyzed using groupings or windows of data to identify anomalous features in the time-average values. Anomalous features can be identified based on a threshold value generated from the analysis. Based on identification of an anomalous feature, a corrective action can be taken. For example, when the monitored condition is the pressure drop across a catalyst bed, detection of an anomaly can indicate the time to initiate a wash process for the catalyst bed before a large drop in catalyst activity occurs. By detecting an anomaly at an earlier point in time, a wash cycle can be initiated earlier so that the wash is more effective at restoring the catalyst bed to a desired condition.
Abstract:
Method for identifying geologic features from seismic data (11) using seismic anomaly detection by a double-windowed statistical analysis. Subtle features that may be obscured using a single window on the data are made identifiable using two moving windows of user-selected size and shape: a pattern window located within a sampling window larger than the pattern window (12). If Gaussian statistics are assumed, the statistical analysis may be performed by computing mean and covariance matrices for the data within the pattern window in its various positions within the sampling window (13). Then a specific measure of degree of anomaly for each voxel such as a residue value may be computed for each sampling window using its own mean and covariance matrix (14), and finally the resulting residue volume may be analyzed, with or without thresholding, for physical features indicative of hydrocarbon potential (15).
Abstract:
Methods and systems for controlling drilling operations include using a statistical model to identify at least two controllable drilling parameters having significant correlation to one or more drilling performance measurements. The methods and systems further generate operational recommendations for at least two controllable drilling parameters based at least in part on the statistical model. The operational recommendations are selected to optimize one or more drilling performance measurements.
Abstract:
Techniques and systems for planning of wireless networks are described. A system according to an aspect of the present invention receives inputs describing traffic statistics for a wireless network and computes network specifications. The system uses the traffic statistics and network specifications as inputs to a computationally tractable model used to compute parameters for the user level performance of the wireless network. The model may suitably be a processor sharing queuing model. The model employed by the planning system allows analytical solution for the desired user level parameters, given the characteristics and conditions entered as inputs and the intended network layout characteristics. Once a set of user level performance parameters has been computed, the values of the parameters are examined to determine if they meet predetermined requirements, in an iterative process continuing until a set of specifications has been developed that produces parameters meeting the requirements.