摘要:
A method for finding clusters of units in high-dimensional data having the steps of determining dense units in selected subspaces within a data space of the high-dimensional data, determining each cluster of dense units that are connected to other dense units in the selected subspaces within the data space, determining maximal regions covering each cluster of connected dense units, determining a minimal cover for each cluster of connected dense units, and identifying the minimal cover for each cluster of connected dense units.
摘要:
The present invention relates to a process for the cryogenic distillation of air in a distillation column system that contains at least one distillation column wherein the boil-up at the bottom of the distillation column producing the oxygen product is provided by condensing a stream whose nitrogen concentration is equal to or greater than that in the feed air stream. The process of the present invention comprises the steps of: (a) generating work energy which is at least ten percent (10%) of the overall refrigeration demand of the distillation column system; (b) work expanding a process stream to produce additional work energy such that the total work generated along with step (a) exceeds the total refrigeration demand of the cryogenic plant; and (c) using the work which is generated in excess of the refrigeration need of the distillation column system to cold compress a process stream at a temperature lower than the ambient temperature.
摘要:
A system and method for discovering similar time sequences in a database of time sequences includes a computer-implemented program which first breaks each sequence into small windows. The windows from the first sequence are compared to selected windows from the second sequence to determine which windows are similar. Pairs of similar windows are then stitched together when certain stitching constraints are met to establish pairs of similar subsequences. Likewise, pairs of similar subsequences are stitched together, and the lengths of the stitched subsequences are then compared to the overall length of the time sequences to determine whether the time sequences meet a similarity criteria.
摘要:
A method and system for performing spatial proximity joins on high-dimensional points representing data objects of a database in parallel in a multiprocessor system. The method comprises the steps of: partitioning the data points among the processors; creating index structures for the data points of the processors in parallel; assigning the join operations to the processors using the index structures; and simultaneously redistributing and joining the data points in the processors in parallel based on a predetermined joining condition. An efficient data structure, .epsilon.-K-D-B tree, is used to provide fast access to the high-dimensional points and to minimize system storage requirements. The invention achieves fast response time and requires minimum storage space by having structurally identical indices among the processors, assigning workload based on the join costs, and redistributing the data points among the processors while joining the data whenever possible.
摘要:
A process is set forth for the cryogenic distillation of an air feed to produce at least two oxygen-rich gaseous streams having different oxygen purities. The process uses a mixing column system in addition to a distillation column system. A key to the process is that at least two oxygen-rich liquid streams having different oxygen purities are transferred from the distillation column system to the mixing column system in order to produce the oxygen-rich gaseous streams.
摘要:
A system and method for mining databases includes a computer-implemented program which identifies patterns of transaction sequences that are stored in a database and which recur in the database with a user-defined regularity. The invention first identifies which sequences are large, i.e., which recur with the defined regularity, and then determines which sequences are maximal, i.e., which large sequences are not subsets of other large sequences. The set of maximal large sequences is returned to the user to indicate recurring purchasing patterns over time.
摘要:
A method and system are disclosed for generating a decision-tree classifier from a training set of records, independent of the system memory size. The method comprises the steps of: generating an attribute list for each attribute of the records, sorting the attribute lists for numeric attributes, and generating a decision tree by repeatedly partitioning the records using the attribute lists. For each node, split points are evaluated to determine the best split test for partitioning the records at the node. Preferably, a gini index and class histograms are used in determining the best splits. The gini index indicates how well a split point separates the records while the class histograms reflect the class distribution of the records at the node. Also, a hash table is built as the attribute list of the split attribute is divided among the child nodes, which is then used for splitting the remaining attribute lists of the node. The created tree is further pruned based on the MDL principle, which encodes the tree and split tests in an MDL-based code, and determines whether to prune and how to prune each node based on the code length of the node.
摘要:
The present invention is directed to two embodiments of a process for recycling an impure argon effluent from a silicon crystal growing furnace using cryogenics. The first embodiment uses cryogenic distillation techniques, and the second embodiment uses cryogenic adsorption, both of which use catalytic treatments and adsorption in conjunction with their cryogenic process steps to provide a pure argon recycle stream for a silicon crystal growth furnace.
摘要:
A fluid mixture is separated by distillation in a two column system in which the feed is prefractionated in a first column having at least one separation stage above the feed and the prefractionator bottoms provides feed to a second column operating at a lower pressure. Cooling for condensing the overhead vapor of the first column is provided by indirect heat exchange with a flashed portion of the feed or with an intermediate fluid obtained from the second column. The two-column system is readily combined with a high pressure column in a three-column distillation system for separating air which is particularly useful for integration with a gasification combined cycle combustion turbine system. Optionally, three nitrogen products can be produced at three different pressures.
摘要:
A process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a plurality of adsorbent beds containing an adsorbent selective for the more strongly adsorbable component using pressurization by product end to product end pressure equalization between beds simultaneous with cocurrent ambient and elevated pressure feed pressurization, coproduction of product and purge gas, and cocurrent depressurization for pressure equalization gas simultaneous with countercurrent evacuation. Oxygen product can be recovered from air at high recovery using the process.