317,364 research outputs found
Grounded Language Interpretation of Robotic Commands through Structured Learning
The presence of robots in everyday life is increasing day by day at a growing pace. Industrial and working environments, health-care assistance in public or domestic areas can benefit from robots' services to accomplish manifold tasks that are difficult and annoying for humans. In such scenarios, Natural Language interactions, enabling collaboration and robot control, are meant to be situated, in the sense that both the user and the robot access and make reference to the environment. Contextual knowledge may thus play a key role in solving inherent ambiguities of grounded language as, for example, the prepositional phrase attachment. In this work, we present a linguistic pipeline for semantic processing of robotic commands, that combines discriminative structured learning, distributional semantics and contextual evidence extracted from the working environment. The final goal is to make the interpretation process of linguistic exchanges depending on physical, cognitive and language-dependent aspects. We present, formalize and discuss an adaptive Spoken Language Understanding chain for robotic commands, that explicitly depends on the operational context during both the learning and processing stages. The resulting framework allows to model heterogeneous information concerning the environment (e.g., positional information about the objects and their properties) and to inject it in the learning process. Empirical results demonstrate a significant contribution of such additional dimensions, achieving up to a 25% of relative error reduction with respect to a pipeline that only exploits linguistic evidence
Using P3P in a web services-based context-aware application platform
This paper describes a proposal for a privacy control architecture to be applied in the WASP project. The WASP project aims to develop a context-aware service platform on top of 3G networks, using web services technology. The proposed privacy control architecture is based on the P3P privacy policy description standard defined by W3C. The paper identifies extensions to P3P and its associated preference expression language APPEL that are needed to operate in a context-aware environment
Keeping Context In Mind: Automating Mobile App Access Control with User Interface Inspection
Recent studies observe that app foreground is the most striking component
that influences the access control decisions in mobile platform, as users tend
to deny permission requests lacking visible evidence. However, none of the
existing permission models provides a systematic approach that can
automatically answer the question: Is the resource access indicated by app
foreground? In this work, we present the design, implementation, and evaluation
of COSMOS, a context-aware mediation system that bridges the semantic gap
between foreground interaction and background access, in order to protect
system integrity and user privacy. Specifically, COSMOS learns from a large set
of apps with similar functionalities and user interfaces to construct generic
models that detect the outliers at runtime. It can be further customized to
satisfy specific user privacy preference by continuously evolving with user
decisions. Experiments show that COSMOS achieves both high precision and high
recall in detecting malicious requests. We also demonstrate the effectiveness
of COSMOS in capturing specific user preferences using the decisions collected
from 24 users and illustrate that COSMOS can be easily deployed on smartphones
as a real-time guard with a very low performance overhead.Comment: Accepted for publication in IEEE INFOCOM'201
ConXsense - Automated Context Classification for Context-Aware Access Control
We present ConXsense, the first framework for context-aware access control on
mobile devices based on context classification. Previous context-aware access
control systems often require users to laboriously specify detailed policies or
they rely on pre-defined policies not adequately reflecting the true
preferences of users. We present the design and implementation of a
context-aware framework that uses a probabilistic approach to overcome these
deficiencies. The framework utilizes context sensing and machine learning to
automatically classify contexts according to their security and privacy-related
properties. We apply the framework to two important smartphone-related use
cases: protection against device misuse using a dynamic device lock and
protection against sensory malware. We ground our analysis on a sociological
survey examining the perceptions and concerns of users related to contextual
smartphone security and analyze the effectiveness of our approach with
real-world context data. We also demonstrate the integration of our framework
with the FlaskDroid architecture for fine-grained access control enforcement on
the Android platform.Comment: Recipient of the Best Paper Awar
Dorsal-CA1 hippocampal neuronal ensembles encode nicotine-reward contextual associations
Natural and drug rewards increase the motivational valence of stimuli in the environment that, through Pavlovian learning mechanisms, become conditioned stimuli that directly motivate behavior in the absence of the original unconditioned stimulus. While the hippocampus has received extensive attention for its role in learning and memory processes, less is known regarding its role in drug-reward associations. We used in vivo Ca2+ imaging in freely moving mice during the formation of nicotine preference behavior to examine the role of the dorsal-CA1 region of the hippocampus in encoding contextual reward-seeking behavior. We show the development of specific neuronal ensembles whose activity encodes nicotine-reward contextual memories and that are necessary for the expression of place preference. Our findings increase our understanding of CA1 hippocampal function in general and as it relates to reward processing by identifying a critical role for CA1 neuronal ensembles in nicotine place preference
Security in Pervasive Computing: Current Status and Open Issues
Million of wireless device users are ever on the move, becoming more dependent on their PDAs, smart phones, and other handheld devices. With the advancement of pervasive computing, new and unique capabilities are available to aid mobile societies. The wireless nature of these devices has fostered a new era of mobility. Thousands of pervasive devices are able to arbitrarily join and leave a network, creating a nomadic environment known as a pervasive ad hoc network. However, mobile devices have vulnerabilities, and some are proving to be challenging. Security in pervasive computing is the most critical challenge. Security is needed to ensure exact and accurate confidentiality, integrity, authentication, and access control, to name a few. Security for mobile devices, though still in its infancy, has drawn the attention of various researchers. As pervasive devices become incorporated in our day-to-day lives, security will increasingly becoming a common concern for all users - - though for most it will be an afterthought, like many other computing functions. The usability and expansion of pervasive computing applications depends greatly on the security and reliability provided by the applications. At this critical juncture, security research is growing. This paper examines the recent trends and forward thinking investigation in several fields of security, along with a brief history of previous accomplishments in the corresponding areas. Some open issues have been discussed for further investigation
Privacy in Public and the contextual conditions of agency
Current technology and surveillance practices make behaviors traceable to persons in unprecedented ways. This causes a loss of anonymity and of many privacy measures relied on in the past. These de facto privacy losses are by many seen as problematic for individual psychology, intimate relations and democratic practices such as free speech and free assembly. I share most of these concerns but propose that an even more fundamental problem might be that our very ability to act as autonomous and purposive agents relies on some degree of privacy, perhaps particularly as we act in public and semi-public spaces. I suggest that basic issues concerning action choices have been left largely unexplored, due to a series of problematic theoretical assumptions at the heart of privacy debates. One such assumption has to do with the influential conceptualization of privacy as pertaining to personal intimate facts belonging to a private sphere as opposed to a public sphere of public facts. As Helen Nissenbaum has pointed out, the notion of privacy in public sounds almost like an oxymoron given this traditional private-public dichotomy. I discuss her important attempt to defend privacy in public through her concept of âcontextual integrity.â Context is crucial, but Nissenbaumâs descriptive notion of existing norms seems to fall short of a solution. I here agree with Joel Reidenbergâs recent worries regarding any approach that relies on âreasonable expectationsâ . The problem is that in many current contexts we have no such expectations. Our contexts have already lost their integrity, so to speak. By way of a functional and more biologically inspired account, I analyze the relational and contextual dynamics of both privacy needs and harms. Through an understanding of action choice as situated and options and capabilities as relational, a more consequence-oriented notion of privacy begins to appear. I suggest that privacy needs, harms and protections are relational. Privacy might have less to do with seclusion and absolute transactional control than hitherto thought. It might instead hinge on capacities to limit the social consequences of our actions through knowing and shaping our perceptible agency and social contexts of action. To act with intent we generally need the ability to conceal during exposure. If this analysis is correct then relational privacy is an important condition for autonomic purposive and responsible agencyâparticularly in public space. Overall, this chapter offers a first stab at a reconceptualization of our privacy needs as relational to contexts of action. In terms of ârights to privacyâ this means that we should expand our view from the regulation and protection of the information of individuals to questions of the kind of contexts we are creating. I am here particularly interested in what I call âunbounded contextsâ, i.e. cases of context collapses, hidden audiences and even unknowable future agents
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