3,506 research outputs found
A quantum logic-based query processing approach for extending relational query languages
Evaluating a traditional database query against a data tuple returns a true on match and a false on mismatch. Unfortunately, there are many application scenarios where such an evaluation is not possible or does not adequately meet users needs. A further problematic application area is text retrieval where in general finding a complete match is impossible. Thus, there is a need for incorporating impreciseness and proximity into a logic-based query language: Objects fulfill such a similarity condition to a certain degree which is expressed by a result value out of the interval [0, 1]. In this work we will sketch a quantum logic-based approach, which provides the combination of classical Boolean predicates and similarity conditions into one integrating formalism
Semantics, Modelling, and the Problem of Representation of Meaning -- a Brief Survey of Recent Literature
Over the past 50 years many have debated what representation should be used
to capture the meaning of natural language utterances. Recently new needs of
such representations have been raised in research. Here I survey some of the
interesting representations suggested to answer for these new needs.Comment: 15 pages, no figure
On the probabilistic logical modelling of quantum and geometrically-inspired IR
Information Retrieval approaches can mostly be classed into probabilistic, geometric or logic-based. Recently, a new unifying framework for IR has emerged that integrates a probabilistic description within a geometric framework, namely vectors in Hilbert spaces. The geometric model leads naturally to a predicate logic over linear subspaces, also known as quantum logic. In this paper we show the relation between this model and classic concepts such as the Generalised Vector Space Model, highlighting similarities and differences. We also show how some fundamental components of quantum-based IR can be modelled in a descriptive way using a well-established tool, i.e. Probabilistic Datalog
Synergy between Quantum Computers and Databases
Academia, industry, and societies are showing increasing interest in the possibilities of quantum computing. The research in the intersection of quantum computing and databases is still in its initial steps. This work represents several crucial data management and query processing problems that will benefit from quantum computing. We outline how quantum computing will tackle these challenges and what kind of outcomes and speed-ups we expect. We discuss the position of quantum computing in data management and raise awareness of possible security threats in encryption. We aim to be realistic and point out technical difficulties that currently restrict implementations.Peer reviewe
‘Enhanced Encryption and Fine-Grained Authorization for Database Systems
The aim of this research is to enhance fine-grained authorization and encryption
so that database systems are equipped with the controls necessary to help
enterprises adhere to zero-trust security more effectively. For fine-grained
authorization, this thesis has extended database systems with three new
concepts: Row permissions, column masks and trusted contexts. Row
permissions and column masks provide data-centric security so the security
policy cannot be bypassed as with database views, for example. They also
coexist in harmony with the rest of the database core tenets so that enterprises
are not forced to compromise neither security nor database functionality. Trusted
contexts provide applications in multitiered environments with a secure and
controlled manner to propagate user identities to the database and therefore
enable such applications to delegate the security policy to the database system
where it is enforced more effectively. Trusted contexts also protect against
application bypass so the application credentials cannot be abused to make
database changes outside the scope of the application’s business logic. For
encryption, this thesis has introduced a holistic database encryption solution to
address the limitations of traditional database encryption methods. It too coexists
in harmony with the rest of the database core tenets so that enterprises are not
forced to choose between security and performance as with column encryption,
for example. Lastly, row permissions, column masks, trusted contexts and holistic
database encryption have all been implemented IBM DB2, where they are relied
upon by thousands of organizations from around the world to protect critical data
and adhere to zero-trust security more effectively
Bridging the Gap Between General-Purpose and Domain-Specific Compilers with Synthesis
This paper describes a new approach to program optimization that allows general purpose code to benefit from the optimization power of domain-specific compilers. The key to this approach is a synthesis-based technique to raise the level of abstraction of general-purpose code to enable aggressive domain-specific optimizations.
We have been implementing this approach in an extensible system called Herd. The system is designed around a collection of parameterized kernel translators. Each kernel translator is associated with a domain-specific compiler, and the role of each kernel translator is to scan the input code in search of code fragments that can be optimized by the domain-specific compiler embedded within each kernel translator. By leveraging general synthesis technology, it is possible to have a generic kernel translator that can be specialized by compiler developers for each domain-specific compiler, making it easy to build new domain knowledge into the overall system.
We illustrate this new approach to build optimizing compilers in two different domains, and highlight research challenges that need to be addressed in order to achieve the ultimate vision
Programming Languages and Systems
This open access book constitutes the proceedings of the 30th European Symposium on Programming, ESOP 2021, which was held during March 27 until April 1, 2021, as part of the European Joint Conferences on Theory and Practice of Software, ETAPS 2021. The conference was planned to take place in Luxembourg and changed to an online format due to the COVID-19 pandemic. The 24 papers included in this volume were carefully reviewed and selected from 79 submissions. They deal with fundamental issues in the specification, design, analysis, and implementation of programming languages and systems
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