many of the current policy-based management systems implement policies that depend on dynamic operational environment contexts. The existing formal-based approaches for enforcing security policies are mainly expressed...
详细信息
ISBN:
(纸本)9781467388450
many of the current policy-based management systems implement policies that depend on dynamic operational environment contexts. The existing formal-based approaches for enforcing security policies are mainly expressed using first-order logic. A major drawback of using first-order logic in implementing dynamic policies is that new observations cannot override previously inferred consequences. In fact, a security system whose enterprise policies are implemented using first-order logic is required to have complete access to data in advance in order to be able to perform an informed reasoning and enforce restricting policies. As a major problem, the systems designed based on these first order logic-based approaches are often static, inflexible, and hard to manage and scale. This paper introduces an approach for expressing and enforcing adaptive access control policies dynamically. The paper presents a non-monotonic formal approach based on answer set programming where default policies are explicitly separated from context-dependent and exception policies that often occur in dynamic systems and in particular when the required context data are unavailable ahead of time. The results of presented case study demonstrate the flexibility of the proposed approach compared to the first order logic-based context-sensitive approaches as implemented in Organizational-Based Access Control (ORBAC) model.
This paper presents the concept of parallelisation of a solver for answer set programming (ASP). While there already exist some approaches to parallel ASP solving, there was a lack of a parallel version of the powerfu...
详细信息
ISBN:
(纸本)9783642037696
This paper presents the concept of parallelisation of a solver for answer set programming (ASP). While there already exist some approaches to parallel ASP solving, there was a lack of a parallel version of the powerful clasp solver. We implemented a parallel version of clasp based on message-passing. Experimental results on Blue Gene P/L indicate the potential of such an approach.
Machine Ethics is a newly emerging interdisciplinary field which is concerned with adding an ethical dimension to Artificial Intelligent (AI) agents. In this paper we address the problem of representing and acquiring ...
详细信息
ISBN:
(数字)9783030492106
ISBN:
(纸本)9783030492090;9783030492106
Machine Ethics is a newly emerging interdisciplinary field which is concerned with adding an ethical dimension to Artificial Intelligent (AI) agents. In this paper we address the problem of representing and acquiring rules of codes of ethics in the online customer service domain. The proposed solution approach relies on the non-monotonic features of answer set programming (ASP) and applies ILP. The approach is illustrated by means of examples taken from the preliminary tests conducted with a couple of state-of-the-art ILP algorithms for learning ASP rules.
Incorporating commonsense and coping with dynamic knowledge are key capabilities of service robots to efficiently interact with humans. In the presented system, we demonstrate how to equip service robots with commonse...
详细信息
ISBN:
(纸本)9783030358884;9783030358877
Incorporating commonsense and coping with dynamic knowledge are key capabilities of service robots to efficiently interact with humans. In the presented system, we demonstrate how to equip service robots with commonsense knowledge and the dynamic reasoning capabilities of answer set programming (ASP). We investigated the response of our system to basic human needs and evaluated the viability and scalability of the combination of the commonsense knowledge database ConceptNet 5 and the ASP solver Clingo. Our results show the flexibility and versatility of our approach. Further, we identified the need for research on scalability in case of environments that are abundant with objects.
Neuro-Symbolic AI (NeSy) holds promise to ensure the safe deployment of AI systems, as interpretable symbolic techniques provide formal behaviour guarantees. The challenge is how to effectively integrate neural and sy...
详细信息
ISBN:
(纸本)9783031711664;9783031711671
Neuro-Symbolic AI (NeSy) holds promise to ensure the safe deployment of AI systems, as interpretable symbolic techniques provide formal behaviour guarantees. The challenge is how to effectively integrate neural and symbolic computation, to enable learning and reasoning from raw data. Existing pipelines that train the neural and symbolic components sequentially require extensive labelling, whereas end-to-end approaches are limited in terms of scalability, due to the combinatorial explosion in the symbol grounding problem. In this paper, we leverage the implicit knowledge within foundation models to enhance the performance in NeSy tasks, whilst reducing the amount of data labelling and manual engineering. We introduce a new architecture, called NeSyGPT, which fine-tunes a vision-language foundation model to extract symbolic features from raw data, before learning a highly expressive answerset program to solve a downstream task. Our comprehensive evaluation demonstrates that NeSyGPT has superior accuracy over various baselines, and can scale to complex NeSy tasks. Finally, we highlight the effective use of a large language model to generate the programmatic interface between the neural and symbolic components, significantly reducing the amount of manual engineering required. The Appendix is presented in the longer version of this paper, which contains additional results and analysis [8].
In the last decades, Deep Learning (DL)-based approaches have been fruitfully employed in many tasks, such as providing valuable support to computer-aided diagnosis and medicine. However, DL-based approaches are known...
详细信息
ISBN:
(纸本)9783031157073;9783031157066
In the last decades, Deep Learning (DL)-based approaches have been fruitfully employed in many tasks, such as providing valuable support to computer-aided diagnosis and medicine. However, DL-based approaches are known to suffer from some limitations;for instance, they lack of proper means for providing clear explanations and interpretations of the results, or explicitly including available knowledge to drive decisions. In this work, we present DeduDeep, the prototypical implementation of a framework explicitly conceived with the aim of tackling such limitations by making use of deductive declarative formalisms. In particular, the framework aims at enabling the declarative encoding of explicit knowledge, and, by relying on the use of answer set programming (ASP), taking advantage of it for driving decisions taken by neural networks and refining the output. The framework has been tested using different artificial neural networks tailored to semantic segmentation tasks over Laryngeal Endoscopic Images and Freiburg Sitting People Images.
. Weighted knowledge bases for description logics with typicality provide a logical interpretation of MultiLayer Perceptrons, based on a "concept-wise" multi-preferential semantics. On the one hand, in the f...
详细信息
. Weighted knowledge bases for description logics with typicality provide a logical interpretation of MultiLayer Perceptrons, based on a "concept-wise" multi-preferential semantics. On the one hand, in the finitely many-valued case, answer set programming (ASP) has been shown to be suitable for addressing defeasible reasoning from weighted knowledge bases for the boolean fragment of ALC. . On the other hand, the semantics of weighted knowledge bases with typicality, in their different variants, have suggested some new gradual argumentation semantics, as well as an approach for defeasible reasoning over a weighted argumentation graph, building on the gradual semantics and, specifically on the (p-coherent semantics. In this paper, we explore the relationships between weighted knowledge bases and weighted argumentation graphs, to develop proof methods for defeasible reasoning over an argumentation graph under the (p-coherent semantics, in the finitely-valued case. We establish a mapping from a weighted argumentation graph to a weighted knowledge base as well as a lower bound on the complexity of the problem of verifying graded implications over an argumentation graph in the (p-coherent semantics. We also consider a mapping from weighted knowledge bases to weighted argumentation graphs, and provide an ASP implementation and some experimental results.
State-of-the-art service robots that fetch a cup of coffee and clean up rooms require cognitive skills such as learning, planning, and reasoning. Especially reasoning in dynamic and human populated environments demand...
详细信息
ISBN:
(数字)9783319935812
ISBN:
(纸本)9783319935812;9783319935805
State-of-the-art service robots that fetch a cup of coffee and clean up rooms require cognitive skills such as learning, planning, and reasoning. Especially reasoning in dynamic and human populated environments demands for novel approaches that can handle comprehensive and fluent knowledge bases. Our long-term objective is an autonomous robotic team that is capable of handling dynamic and domestic environments. Therefore, we combined ALICA - A Language for Interactive Cooperative Agents - with the answer set programming solver Clingo. The answer set programming approach offers multi-shot solving techniques and non-monotonic stable model semantics, but requires to keep the Module Property satisfied. We developed an automatic satisfaction of the Module Property and chose topological path planning as our evaluation scenario. We utilised the Region Connection Calculus as the underlying formalism of our evaluation and investigated the scalability of our implementation. The results show that our approach handles dynamic environments and scales up to appropriately large problem sizes while automatically satisfying the Module Property.
Drug-drug interaction (DDI) study is an important aspect of therapy management and drug efficacy. DDI study investigates how drugs interact with each other and determine whether these interactions may lead to dire eff...
详细信息
ISBN:
(纸本)9781479940035
Drug-drug interaction (DDI) study is an important aspect of therapy management and drug efficacy. DDI study investigates how drugs interact with each other and determine whether these interactions may lead to dire effects or nullify the therapeutic effects of each other. In this paper we model metabolic pathways of drugs that include the reaction effects between drugs and the related enzymes. By modeling the reaction effects, our model captures the degree of the effects of the interacting drugs. We introduce a novel methodology that combines semantics, ontology to model the concepts and interactions, and answer set programming for temporal reasoning. We illustrate our method by inferring the effects of DDI among three drugs clozapine, olanzapine and fluvoxamine.
First proposed by Wang and Li in 2007, workflow resiliency is a policy analysis for ensuring that, even when an adversarial environment removes a subset of workers from service, a workflow can still be instantiated to...
详细信息
ISBN:
(纸本)9781450360999
First proposed by Wang and Li in 2007, workflow resiliency is a policy analysis for ensuring that, even when an adversarial environment removes a subset of workers from service, a workflow can still be instantiated to satisfy all the security constraints. Wang and Li proposed three notions of workflow resiliency: static, decremental, and dynamic resiliency. While decremental and dynamic resiliency are both PSPACE-complete, Wang and Li did not provide a matching lower and upper bound for the complexity of static resiliency. The present work begins with proving that static resiliency is Pi(p)(2)-complete, thereby bridging a long-standing complexity gap in the literature. In addition, a fourth notion of workflow resiliency, one-shot resiliency, is proposed and shown to remain in the third level of the polynomial hierarchy. This shows that sophisticated notions of workflow resiliency need not be PSPACE-complete. Lastly, we demonstrate how to reduce static and one-shot resiliency to answer set programming (ASP), a modern constraint-solving technology that can be used for solving reasoning tasks in the lower levels of the polynomial hierarchy. In summary, this work demonstrates the value of focusing on notions of workflow resiliency that reside in the lower levels of the polynomial hierarchy.
暂无评论