32047
Constructing a Generic Natural Language Interface for an XML Database
We describe the construction of a generic natural language query interface to an XML database. Our interface can accept an arbitrary English sentence as a query, which can be quite complex and include aggregation, nesting, and value joins, among other things. This query is translated, potentially after reformulation, into an XQuery expression. The translation is based on mapping grammatical proximity of natural language parsed tokens in the parse tree of the query sentence to proximity of corresponding elements in the XML data to be retrieved. Our experimental assessment, through a user study, demonstrates that this type of natural language interface is good enough to be usable now, with no restrictions on the application domain.
16207650
Term Disambiguation in Natural Language Query for XML
Converting a natural language query sentence into a formal database query is a major challenge. We have constructed NaLIX, a natural language interface for querying XML data. Through our experience with NaLIX, we find that failures in natural language query understanding can often be dealt with as ambiguities in term meanings. These failures are typically the result of either the user's poor knowledge of the database schema or the system's lack of linguistic coverage. With automatic term expansion techniques and appropriate interactive feedback, we are able to resolve these ambiguities. In this paper, we describe our approach and present results demonstrating its effectiveness.
1293275
Getting work done on the web: supporting transactional queries
Many searches on the web have a transactional intent. We argue that pages satisfying transactional needs can be distinguished from the more common pages that have some information and links, but cannot be used to execute a transaction. Based on this hypothesis, we provide a recipe for constructing a transaction annotator. By constructing an annotator with one corpus and then demonstrating its classification performance on another,we establish its robustness. Finally, we show experimentally that a search procedure that exploits such pre-annotation greatly outperforms traditional search for retrieving transactional pages.
1877430
Mobile Robot Navigation Using Particle Swarm Optimization and Adaptive NN
This paper presents a novel design for mobile robot using particle swarm optimization (PSO) and adaptive NN control. The adaptive NN control strategy guarantees that robot with nonholonomic constraints can follow smooth trajectories. Based on this property, a PSO algorithm for path planning is proposed. The path planning generates smooth path with low computational cost to avoid obstacles, so that robot can use smooth control strategy to track the trajectory.
1475500
Efficient XML Data Management: An Analysis
With XML rapidly gaining popularity as the standard for data exchange on the World Wide Web, a variety of XML management systems (XMLMS) are becoming available. The choice of an XMLMS is made difficult by the significant difference in the expressive power of the queries and the performance shown by these XMLMS. Most XMLMS are legacy systems (mostly relational) extended to load, query, and publish data in XML format. A few are native XMLMS and capture all the characteristics of XML data representation. This paper looks at expressive power and efficiency of various XMLMS. The performance analysis relies on the testbed provided by XOO7, a benchmark derived from OO7 to capture both data and document characteristics of XML. We present efficiency results for two native XMLMS, an XML-enabled semistructured data management system and an XML-enabled RDBMS, which emphasize the need for a delicate balance between the data-centric and document-centric aspects of XML query processing.
6040880
Rupture degree of graphs
We introduce a new graph parameter, the rupture degree. The rupture degree for a complete graph K n is defined as 1−n, and the rupture degree for an incomplete connected graph G is defined by r(G)=max{ω(G−X)−|X|−m(G−X):X⊂V(G), ω(G−X)>1}, where ω(G−X) is the number of components of G−X and m(G−X) is the order of a largest component of G−X. It is shown that this parameter can be used to measure the vulnerability of networks. Rupture degrees of several specific classes of graphs are determined. Formulas for the rupture degree of join graphs and some bounds of the rupture degree are given. We also obtain some Nordhaus–Gaddum type results for the rupture degree.
2685399
EaseDB: a cache-oblivious in-memory query processor
We propose to demonstrate EaseDB, the first cache-oblivious queryprocessor for in-memory relational query processing. The cache-oblivious notion from the theory community refers to the property that no parameters in an algorithm or a data structure need to be tuned for a specific memory hierarchy for optimality. As a result, EaseDB automatically optimizes the cache performance as well as the overall performance of query processing on any memory hierarchy. We have developed a visualization interface to show the detailed performance of EaseDB in comparison with its cache-conscious counterpart, with both the parameters in the cache-conscious algorithms and the hardware platforms varied.
2533092
State-preserving vs. non-state-preserving leakage control in caches
This paper compares the effectiveness of state-preserving and non-state-preserving techniques for leakage control in caches by comparing drowsy cache and gated-V/sub ss/ for data caches using 70nm technology parameters. To perform the comparison, we introduce "HotLeakage", a new architectural model for subthreshold and gate leakage that explicitly models the effects of temperature, voltage, and parameter variations, and has the ability to recalculate leakage currents dynamically as temperature and voltage change at runtime due to operating conditions, DVS techniques, etc. By comparing drowsy-cache and gated-V/sub ss/ at different L2 latencies and different gate oxide thickness values, we are able to identify a range of operating parameters at which gated-V/sub ss/ is more energy efficient than drowsy-cache, even though gated-V/sub ss/ does not preserve data in cache lines that have been deactivated. We are also able to show potential further benefits of gated-V/sub ss/ if an effective dynamic adaptation technique can be found. These results debunk a fairly widespread belief that state-preserving techniques are inherently superior to non-state-preserving techniques.