30 resultados para correctness verification

em Deakin Research Online - Australia


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Database query verification schemes provide correctness guarantees for database queries. Typically such guarantees are required and advisable where queries are executed on untrusted servers. This need to verify query results, even though they may have been executed on one’s own database, is something new that has arisen with the advent of cloud services. The traditional model of hosting one’s own databases on one’s own servers did not require such verification because the hardware and software were both entirely within one’s control, and therefore fully trusted. However, with the economical and technological benefits of cloud services beckoning, many are now considering outsourcing both data and execution of database queries to the cloud, despite obvious risks. This survey paper provides an overview into the field of database query verification and explores the current state of the art in terms of query execution and correctness guarantees provided for query results. We also provide indications towards future work in the area.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Database query verification schemes attempt to provide authenticity, completeness, and freshness guarantees for queries executed on untrusted cloud servers. A number of such schemes currently exist in the literature, allowing query verification for queries that are based on matching whole values (such as numbers, dates, etc.) or for queries based on keyword matching. However, there is a notable gap in the research with regard to query verification schemes for pattern-matching queries. Our contribution here is to provide such a verification scheme that provides correctness guarantees for pattern-matching queries executed on the cloud. We describe a trivial scheme, ȃŸż and show how it does not provide completeness guarantees, and then proceed to describe our scheme based on efficient primitives such as cryptographic hashing and Merkle hash trees along with suffix arrays. We also provide experimental results based on a working prototype to show the practicality of our scheme.Ÿż

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Cyber-physical-social system (CPSS) allows individuals to share personal information collected from not only cyberspace but also physical space. This has resulted in generating numerous data at a user's local storage. However, it is very expensive for users to store large data sets, and it also causes problems in data management. Therefore, it is of critical importance to outsource the data to cloud servers, which provides users an easy, cost-effective, and flexible way to manage data, whereas users lose control on their data once outsourcing their data to cloud servers, which poses challenges on integrity of outsourced data. Many schemes have been proposed to allow a third-party auditor to verify data integrity using the public keys of users. Most of these schemes bear a strong assumption: the auditors are honest and reliable, and thereby are vulnerability in the case that auditors are malicious. Moreover, in most of these schemes, an auditor needs to manage users certificates to choose the correct public keys for verification. In this paper, we propose a secure certificateless public integrity verification scheme (SCLPV). The SCLPV is the first work that simultaneously supports certificateless public verification and resistance against malicious auditors to verify the integrity of outsourced data in CPSS. A formal security proof proves the correctness and security of our scheme. In addition, an elaborate performance analysis demonstrates that the SCLPV is efficient and practical. Compared with the only existing certificateless public verification scheme (CLPV), the SCLPV provides stronger security guarantees in terms of remedying the security vulnerability of the CLPV and resistance against malicious auditors. In comparison with the best of integrity verification scheme achieving resistance against malicious auditors, the communication cost between the auditor and the cloud server of the SCLPV is independent of the size of the processed data, meanwhile, the auditor in the SCLPV does not need to manage certificates.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Kanban Control Systems (KCS) have become a widely accepted form of inventory and production control. The creation of realistic Discrete Events Simulation (DES) models of KCS require specification of both information and material flow. There are several commercially available simulation packages that are able to model these systems although the use of an application specific modelling language provides means for rapid model development. A new Kanban specific simulation language as well as a high-speed execution engine is verified in this paper through the simulation of a single stage single part type production line. A single stage single part KCS is modelled with exhaustive enumeration of the decision variables of container sizes and number of Kanbans. Several performance measures were used; 95% Confidence Interval (CI) of container Flow Time (FT), mean line throughput as well as the Coefficient of Variance (CV) of FT and Cycle Time were used to determine the robustness of the control system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We hereby develop an effective and efficient testing methodology for correctness testing for file recovery tools across different file systems. We assume that the tool tester is familiar with the formats of common file types and has the ability to use the tools correctly. Our methodology first derives a testing plan to minimize the number of runs required to identify the differences in tools with respect to correctness. We also present a case study on correctness testing for file carving tools, which allows us to confirm that the number of necessary testing runs is bounded and our results are statistically sound.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Parameter-Driven Systems (PDS) are widely used in commerce for large-scale applications. Reusability is achieved with a PDS design by relocating implicit control structures in the software and the storage of explicit data in database files. This approach can accommodate various user requirements without tedious modification of the software. In order to specify appropriate parameters in a system, knowledge of both business activities and system behaviour are required. For large, complex software packages, this task becomes time consuming and requires specialist knowledge, yet the consistency and correctness still cannot be guaranteed. My research studied the types of knowledge required and agents involved in the PDS customisation. The work also identified the associated problems and constraints. A solution is proposed and implemented as an Intelligent Assistant prototype than a manual approach. Three areas of achievement have been highlighted: 1. The characteristics and problems of maintaining parameter instances in a PDS are defined. It is found that the verification is not complete with the technical/structural knowledge alone, but a context is necessary to provide semantic information and related business activities (thus the implemented parameters) so that mainline functions can relate with each other. 2. A knowledge-based modelling approach has been proposed and demonstrated via a practical implementation. A Specification Language was designed which can model various types of knowledge in a PDS and encapsulate relationships. The Knowledge-Based System (KBS) developed verifies parameters based on the interpreted model of a given context. 3. The performance of the Intelligent Assistant prototype was well received by the domain specialist from the participating organisation. The modelling and KBS approach developed in my research offers considerable promise in solving practical problems in the software industry.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper examines the different ways in which carbon rights have been verified as property interests. A carbon right is a new and unique form of land interest that confers upon the holder a right to the incorporeal benefit of carbon sequestration on a piece of forested land. Carbon sequestration refers to the absorption from the atmosphere of carbon dioxide by vegetation and soils and the storage of carbon in vegetation and soils. Innovative legislation has been introduced in each state seeking to separate the incorporeal benefit of carbon sequestration from the natural rights flowing from land ownership. The fragmentation of land ownership in this way is a constituent of broader climate change strategies and is particularly important for an Australian emissions trading scheme where carbon rights will acquire value as tradable offsets. This paper will explore the different legislative responses of each state to the proprietary characterisation of the carbon right as a land interest. It will argue that verifying the carbon right as a new statutory property interest, in line with the approach set out in the Carbon Rights Act 2003 (WA), is preferable to aligning it with preconceived categories of common law servitude. By articulating the  carbon right as a new form of statutory interest, unique in status and form, its sui generis character is more accurately reflected. Further, statutory validation of the carbon right as a new land interest is more efficient as legislative rules are more visible and therefore come to the attention of other market participants more quickly and at a lower cost without the burden and complexity associated with expressing the right through the prism of pre-conceived and non-responsive common law forms.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study investigated how the quality of heterosexual relationships was affected by individuals views of themselves, their partners and how they thought their partners viewed them. Relationship quality was more affected by mood and by how respondents thought their partners viewed them, than by the reality of their partner's views.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In previous work, the authors presented a theoretical lower bound on the required number of testing runs for performance testing of digital forensic tools. We also demonstrated a practical method of testing showing how to tolerate both measurement and random errors in order to achieve results close to this bound. In this paper, we extend the previous work to the situation of correctness testing. The contribution of this methodology enables the tester to achieve correctness testing results of high quality from a manageable number of observations and in a dynamic but controllable way. This is of particular interest to forensic testers who do not have access to sophisticated equipment and who can allocate only a small amount of time to testing.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The abolition of riparian entitlements in the early stages of colonial Australia and the vesting of these rights in the Crown represented a turning point for the evolution of private water rights. The extinguishment of common law rights connected to vested land interests and the introduction of new, unaligned statutory entitlements provided a new and fundamentally different system for the creation and regulation of private water entitlements. Unlike riparian entitlements, in the absence of express definition, statutory water entitlements may only be verified as property where such a construction is consistent with the nature and scope of the entitlement. In this respect, the statutory framework has disaggregated the propertisation of water rights from land ownership and linked the process to broader statutory interpretation principles. The shift away from institutional property has generated concerns about the interpretive approaches appropriate for the verification of legislative water entitlements. This article examines the existing interpretive approaches and argues that the blurring of the propertisation process with the separate issue of whether any change or modification of such water rights attracts s 51(xxxi) of the Commonwealth Constitution has produced a situation where core property indicia is increasingly overshadowed by legislative defeasibility. In the recent High Court decision of ICM Agriculture Pty Ltd v Commonwealth, the focus of the majority judgements upon the inherent susceptibility of legislative entitlements to variation or extinguishment acted as a catalyst for the non-propertisation of statutory bore water licences in New South Wales. The emphasis the majority judgements gave to legislative defeasibility precluded a full and balanced assessment of other highly relevant property indicia, in particular the expectation interests of the holders. Conflating property and constitutional evaluation in this way is inappropriate in an era where entitlements to natural resource interests are increasingly statute based and the verification process has significant social and economic repercussions. Determining whether a statutory entitlement constitutes property requires a careful balancing of legislative intent, social and environmental context and individual expectation and the vicissitudes of a regulatory context should not eclipse this process.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper presents a novel driver verification algorithm based on the recognition of handgrip patterns on steering wheel. A pressure sensitive mat mounted on a steering wheel is employed to collect a series of pressure images exerted by the hands of the drivers who intend to start the vehicle. Then, feature extraction from those images is carried out through two major steps: Quad-Tree-based multi-resolution decomposition on the images and Principle Component Analysis (PCA)-based dimension reduction, followed by implementing a likelihood-ratio classifier to distinguish drivers into known or unknown ones. The experimental results obtained in this study show that the mean acceptance rates of 78.15% and 78.22% for the trained subjects and the mean rejection rates of 93.92% and 90.93% to the un-trained ones are achieved in two trials, respectively. It can be concluded that the driver verification approach based on the handgrip recognition on steering wheel is promising and will be further explored in the near future.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper proposes a methodology for determining the shape and ultimately the functionality of objects from intensity images; 2D analytic functions are used to track 3D features during known camera motions. Three analytic functions are proposed that describe the relationship between pairs of points that are either stationary or moving depending on whether the points are on occluding boundaries or otherwise. Many of the problems of correspondence are reduced by using foveation, known camera motion, and active vision methods. The three analytic functions are shown to enable hypothesis refinement of the functionality of a number of 3D objects without full 3D information about the shape.