431369
The Information-Processing Difficulty Of Incremental Parsing
When an incremental parser gets the next word, its expectations about upcoming grammatical structures can change. When a word greatly constrains these grammatical expectations, uncertainty is reduced. This elimination of possibilities constitutes information processing work. Formalizing this notion of information processing work yields a complexity metric that predicts human repetition accuracy scores across a systematic class of linguistic phenomena, the Accessibility Hierarchy of relativizable grammatical relations.
5567072
Surprising Parser Actions and Reading Difficulty
An incremental dependency parser's probability model is entered as a predictor in a linear mixed-effects model of German readers' eye-fixation durations. This dependency-based predictor improves a baseline that takes into account word length, n-gram probability, and Cloze predictability that are typically applied in models of human reading. This improvement obtains even when the dependency parser explores a tiny fraction of its search space, as suggested by narrow-beam accounts of human sentence processing such as Garden Path theory.
7472011
PCFGs with Syntactic and Prosodic Indicators of Speech Repairs
A grammatical method of combining two kinds of speech repair cues is presented. One cue, prosodic disjuncture, is detected by a decision tree-based ensemble classifier that uses acoustic cues to identify where normal prosody seems to be interrupted (Lickley, 1996). The other cue, syntactic parallelism, codifies the expectation that repairs continue a syntactic category that was left unfinished in the reparandum (Levelt, 1983). The two cues are combined in a Treebank PCFG whose states are split using a few simple tree transformations. Parsing performance on the Switchboard and Fisher corpora suggests that these two cues help to locate speech repairs in a synergistic way.
38823802
A Ticket-Based Access Control Architecture for Object Systems
The design and implementation of authorization services for distributed object systems are hindered by the semantic diversity of object models, the brittleness of access control mechanisms, and the lack of design and analysis tools. This paper presents a primitive ticket-based access control architecture that can model a variety of authorization policies. The access control architecture is integrated within a primitive distributed object model that can capture most distributed object languages and systems. The integration provides a common foundation for access control in heterogeneous distributed object systems, instrumental to achieving high assurance secure interoperability.
2505382
Catalytic inference analysis: detecting inference threats due to knowledge discovery
Knowledge discovery in databases can be enhanced by introducing "catalytic relations" conveying external knowledge. The new information catalyzes database inference, manifesting latent channels. Catalytic inference is imprecise in nature, but the granularity of inference may be fine enough to create security compromises. Catalytic inference is computationally intensive. However, it can be automated by advanced search engines that gather and assemble knowledge from information repositories. The relentless information gathering potential of such search engines makes them formidable security threats. This paper presents a formalism for modeling and analyzing catalytic inference in "mixed" databases containing various precise, imprecise and fuzzy relations. The inference formalism is flexible and robust, and well-suited to implementation.
753928
Policy mediation for multi-enterprise environments
Existing software infrastructures and middleware provide uniform security services across heterogeneous information networks. However few, if any, tools exist that support access control policy management for and between large enterprise information networks. Insiders often exploit gaps in policies to mount devastating attacks. This paper presents a Policy Machine and Policy Mediation Architecture for coordinating diverse policies in large information networks. The language-based approach adopted by each of these technologies permits local and global access control policy validation with static analysis and other formal techniques. Together the Policy Machine and Policy Mediation Architecture comprise an effective system for closing policy gaps in multi-enterprise environments.
32535650
Toward Robust and Extensible Automatic Protocol Identification
A fingerprint sensor having a holographic phase grating glued on one right angle surface of a prism is described where a light source oriented normally relative to the hypotenuse surface of the prism illuminates an interface of the grating and finger surface. Incident light rays are refracted and absorbed where ridges of the finger surface contact the grating surface, whereas light rays are totally internally reflected in areas between and pores in finger surface ridges not in contact the grating surface. The reflected light rays, diffracted by the holographic phase grating, propagate normally ( ORTHOGONAL ) back into the right angle prism where they are reflected normally ( ORTHOGONAL ) out the remaining right angle surface of the prism by a second total internal reflection at the internal hypotenuse surface of the prism. The reflected light rays emerging from the sensor contain high contrast, detailed images of the ridges and valleys of the finger surface including pores in the ridges, i.e., a high quality fingerprint image oriented in a plane normal to the optical axis. The holographic phase grating eliminates image distortion due dimensional compression, and there is no necessity for optically correcting astigmatism in the image before capture. Fingerprint images of a quality that allows resolution of pores on the finger surface ridges are reliably obtained making the invented fingerprint sensor ideally suited for providing input to fingerprint recording, recognition and verification systems.