waashk/dblp huggingface dataset:
image domain formalization for content-based image retrieval. this paper proposes a formal representation of the operations required to perform content-based image retrieval (cbir) in large relational databases, using similarity queries. in this paper, we consider similarity as a numerical value obtained comparing a pair of images, which is calculated by a distance (dissimilarity) function. distance functions usually rely on a set of features extracted from each image through a set of image processing algorithms called feature extractors. before extracting features, other image processing algorithms are usually employed to pre-process each image, preparing it for the extractors. usually there are several criteria that can be considered when measuring how much two images are similar. therefore, to compare images in current cbir environments one must define (1) the criteria, (2) the image pre-processing needed before the extractors can be executed, (3) which are those extractors, (4) which features must be considered, (5) and which distance function must be used. all of these definitions must have been set before a comparison can be performed. the complexity of defining how to compare images has lead to the development of systems aiming cbir that allow relatively few options to configure the image comparison operations. moreover, no formal representation of the entire cbir process exists. in this paper we present such a formal environment, where all above-mentioned definitions are represented, entailing the development of flexible and highly-configurable cbir systems. we also report a system developed using this formalism that enables the content-based retrieval of medical images from a hospital database, thus showing results of applying the presented formalism in a real environment.
a transition-based strategy for object-oriented software testing. though time-to-market has become the primary criterion that drives most current software development projects, quality still remains the key concern of critical software development projects, for which the cost of a single bug may involve serious loss or damages. meeting the higher quality level required for such kinds of systems may be achieved only by using sound and rigorous test practices. we present in this paper an integrated platform that uses a formalized version of uml statechart as the basis for rigorous testing of object-oriented programs. the platform adapts and integrates systematic test data generation strategies and associated tools for object-oriented program testing.
a protection scheme for collaborative environments. in collaborative working environments where multiple users use and/or provide multiple services, a more flexible security model is needed. security must be enforced in such environments without affecting usability, scalability, and performance. in this paper, we propose a flexible protection scheme based on the lattice security model that combines information flow and access control mechanisms in order to address privacy and integrity requirements in scalable collaborative environments.
an integrated framework for formal development of open distributed systems. this paper contributes to the discussion on issues related to the formal development of open distributed systems (ods). the deficiencies of traditional formal notations in this setting are highlighted. we argue that there is no single formalism exhibiting all the features required to capture properties of odss. as a solution, we propose an integrated development framework that involves two notations: the unified modeling language (uml) and the prototype verification system (pvs). we discuss the motivation for the choice of these notations, provide an overview of a case tool we have developed to support the proposed framework, and present a case study to demonstrate our approach.
the mt model transformation language. model transformations are recognised as a vital part of model driven development, but current approaches are often simplistic, with few distinguishing features, and frequently lack an implementation. the practical difficulties of implementing an approach inhibit experimentation within the paradigm. in this paper, i present the mt model transformation language which was implemented as a low-cost dsl in the converge programming language. although mt shares several aspects in common with other model transformation languages, an ability to rapidly experiment with the implementation has led mt to contain a number of new features, insights and differences from other approaches.
transparency for polygon based cloud rendering. for the local tv presentation of weather forecast data it is important to have high-quality and fast visualisation of clouds. in this paper we present surface-based transparency computation methods for the high performance visualisation of clouds from data produced by a routine meteorological weather simulation. in contrast to the state-of-the-art volume cloud visualisation we use only hardware-supported polygon-based transparency computation.
plan validation via petri nets in the real-time performers java framework. the real-time performers (rtp) architecture is a framework to design distributed soft real-time systems based on timed plans. timed plans - they define system workflow - contain actions to be executed by distributed components at specified times. an rtp system is controlled by a strategist that may modify plans to adapt system behavior to environment conditions. when a timed plan is changed it may be checked for coherency. this paper presents techniques used in rtp to check timed plans validity through petri nets (pns). these techniques are based on the definition of mappings from rtp topology and plans to pns. once pns are generated, structural and behavioural properties can be calculated and mapped back to the rtp system.
editorial message: special track on organizational engineering. dominated by the behavioral science approach for a long time, information systems research increasingly acknowledges design science as a complementary approach. the systematic design ("engineering") of artifacts is not restricted to information systems components. being the conceptual foundations for information systems requirements, artifacts on the strategic and organizational level have to be engineered as well.
editorial message: special track on organizational engineering (oe). dominated by the behavioral science approach for a long time, information systems research increasingly acknowledges design science as a complementary approach. the systematic design of artifacts is not restricted to information systems components. being the conceptual foundations for information systems requirements, artifacts on the strategic and organizational level have to be engineered as well.
verification of behavioural elements of uml models using b. this paper describes the formal verification of behavioural elements of uml models using b abstract machines. we transform the uml metamodel of behavioural diagrams to b and automatically check proof obligations generated by using the b prover. the correctness of the properties of behavioural elements of uml models is ensured by the well-formedness rules in the uml semantics which are transformed to b as the invariants of abstract machines. we address collaboration diagrams, state-chart diagrams of uml models and study the behavioural elements package (collaboration and state machine) of the uml metamodel as well as well-formedness rules of these packages. we illustrate our approach by a case study.
disclosure risk measures for the sampling disclosure control method. in this paper, we introduce three microdata disclosure risk measures (minimal, maximal and weighted) for sampling disclosure control method. the minimal disclosure risk measure represents the percentage of records that can be correctly identified by an intruder based on prior knowledge of key attribute values. the maximal disclosure risk measure considers the risk associated with probabilistic record linkage for records that are not unique in the masked microdata. the weighted disclosure risk measure allows the data owner to compute the risk of disclosure based on weights associated with different clusters of records. the weights allow a flexible specification of the relative importance of varying cluster sizes in probabilistic record linkage. we show that weighted disclosure risk measure is always between the values of minimal and maximal disclosure risk measures, and moreover for certain values of the weights, the weighted disclosure risk measure is equal to one of the other two measures. using simulated medical data in our experiments, we show that the proposed disclosure risk measures perform as expected in real-life situations.
mining and prediction of temporal navigation patterns for personalized services in e-commerce. with the rapid development of e-commerce, the topic of mining and predicting users' navigation patterns has attracted significant attention due to the wide applications like personalized services in e-commerce. although a number of studies have been done on this topic, few of them take into account the temporal property for web user's navigation patterns. in this paper, we propose a novel method named temporal n-gram (tn-gram) for constructing prediction models of web user navigation by considering the temporality property in web usage evolution. moreover, three kinds of new measures are proposed for evaluating the temporal evolution of navigation patterns under different time periods. through experimental evaluation on both of real-life and simulated datasets, the proposed tn-gram model is shown to outperform other approaches like n-gram modeling in terms of the prediction precision, in particular when the web user's navigating behavior changes with temporal evolution.
an efficient method for mining associated service patterns in mobile web environments. this research presents a new data mining method that can efficiently discover associated service patterns requested by users in mobile web environments. although there exist some studies on data mining in mobile systems in recent years, they were mostly focused on topics like moving path mining or service request log mining and the issue of discovering user's associated service patterns with the locations has not been explored. in particular, this problem becomes more complex when the hierarchical concepts of locations and services are considered. in this work, we propose a new data mining method named two-dimensional multi-level association rules mining, which can efficiently discover the associated service request patterns by taking into account the hierarchical characteristics of the location and service concept. to our best knowledge, this is the first work resolving this research issue. through detailed experimental evaluations under various system conditions, our method was shown to deliver excellent performance in terms of accuracy, completeness, execution efficiency and scalability.
an extendible multidimensional array system for molap. in molap systems, multidimensional arrays are employed to store fact tables dumped from the frontend relational database. on these fact tables, various kinds of statistical computations such as aggregate operations can be performed efficiently by utilizing the fast random accessing capability of arrays. this capability depends on that the size of an employed multidimensional array is fixed in every dimension, so a simple addressing function can be used to access array elements. but, if a new column value emerges after constructing the fact table, the existing fixed size multidimensional array cannot involve the value. in this paper, we provide an extendible multidimensional array system for molap. such an array can extend its size dynamically along an arbitrary dimension without any relocation of existing data. this property enables incremental aggregate operations without relocating any data dumped at the latest time. some problems in making this system work as a basis for molap are stated, and their countermeasures are proposed.
dominance and ranking issues applying interval techniques in pre-negotiations for services. the study looks at the application of preference programming approaches and techniques for decision support during prenegotiations over services. in hierarchical decision analysis models the need for multi-attribute evaluation techniques that may incorporate uncertainties directly in the modeling phase has resulted in the use of the 'interval' approach. with such an approach, preference judgments are presented as ranges including all possible value estimates. this paper reports the results of applying an interval preference programming approach and technique in decision support scenarios for reasoning during pre-negotiations over services. the aim has been to critically evaluate the approach and establish its applicability for ranking multi-dimensional service offers. our experimental results using interval smart, in pre-negotiation decision making scenarios, showed that while the dominance relations among alternatives remained unchanged following the introduction of uncertainty intervals, the rank order and dominance relations of the alternatives may vary as a result of the addition or dropping of new alternatives with inferior values.
som - feature extraction from patient discharge summaries. in each canadian province, hospitals collect information, at discharge, on the hospital stay of each patient. the information is collected in the form of a patient discharge abstract (pda) and sent to the canadian institute for health information. the patient discharge abstract uses the icd-10-ca code standard to outline the assigned diagnoses for the patient's condition and the procedures that were performed. one compulsory piece of information in the patient discharge abstract is the identification of the "most responsible diagnosis" (mrdx) -- that diagnosis considered to be the most significant condition of the patient that caused the greatest length of stay in hospital. this research investigates the potential for automating the process of feature extraction from a narrative patient discharge summary to support the classification of the mrdx for a patient discharge abstract. unsupervised neural networks -- self-organizing maps (som) -- are effective for classification tasks based on noisy input patterns. here a hierarchical architecture of soms is used to identify semantic similarities encoded in the original information and visualize the characteristics of an mrdx.
a framework for automatic generation of web-based data entry applications based on xml. this paper presents a framework for web-based data entry applications. it introduces a method for the conceptional and the navigational design based on a textual specification in the form of an xml-application. this forms the input to a code generation environment allowing for real automated prototyping. the environment produces fully functional skeletons for the web pages. together with the framework classes they can be utilized for testing and for requirements review. they also form the starting point for the work of the presentation design. the main advantage of the framework is a clear separation between the presentation and the business logic. this allows work on each aspect to proceed in parallel along relatively independent but cooperating tracks. the framework has been implemented using java servlets and java server pages.
automated generation of monitors for pattern contracts. while the informal style used to describe design patterns has proven valuable, it is also imprecise. to ensure that patterns are applied correctly, we must also have precise pattern characterizations, and tools for determining whether the appropriate implementation requirements are satisfied. to address this problem, we first present a specification language that captures pattern requirements precisely, as well as the ways in which patterns are specialized for use. second, we present a tool that generates a set of aspect-oriented monitors for a system based on the specifications of the patterns used in its design. the generated aspects are used to monitor the system at runtime to determine whether the appropriate implementation requirements are satisfied.
implications of the topological properties of internet traffic on traffic engineering. in this paper we study the behavior of internet traffic on the as-level topology and discuss its implications on interdomain traffic engineering. we rely on two notable interdomain traffic traces, the first is one month long and the other is one day long. this study shows that interdomain paths are stable for a large majority of the traffic from a routing viewpoint. we show that the aggregation of the traffic occurring on the as-level graph is essentially limited to direct peers, with almost no aggregation occurring at larger as hop distances. furthermore, only part of the as paths of the as-level topology that see a lot of traffic are stable, when considering their presence among the largest as paths on a hourly basis. relying on the largest as paths in traffic over a time window to capture the traffic over the next time interval discloses the important variability of the traffic seen by the largest as paths in traffic. interdomain traffic engineering is hence due to be difficult because of the limited traffic aggregation on the as-level topology and the important topological variability of the traffic for a significant percentage of the total traffic.
fine-grained power management for multithreaded processor cores. we propose a new hardware-based power management technique that is made possible by a multithreaded processor core. a processor-internal scheduler manages frequency and voltage scaling based on the current processor utilization given in percentage of the total performance.
an agreement centric access control mechanism for business to business e-commerce. we argue that matrix-based models are inadequate for regulating business to business (or b2b, for short) e-commerce due to the diversity, complexity and potential large number of commercial agreements that have to be supported. to deal with these issues, we propose in this paper an agreement-centric access control model. the paper introduces the concept of communication agreement (car) as a means for specifying contractual terms, and presents the car enforcement mechanism. we explore the expressive power of the model and show that it can implement regulations which cannot expressed using conventional mechanisms alone. the paper also describes a prototype implementation; the preliminary performance results indicate that the enforcement mechanism is quite affordable, even in its present, experimental stage.
efficient support for enterprise delegation policies. delegation, whereby an entity gives some of its rights to other entities, is considered the cornerstone of decentralized authorization, and many access control frameworks proposed recently make delegation its central tenet. in these frameworks, delegation is commonly viewed as a transfer between two autonomous agents---the grantor and the grantee. but the situation can be considerably more complex, and more challenging, in the case the grantor belongs to an organization. generally, employees are not autonomous agents, but their actions are subject to the regulations of their enterprise. in particular, if an employee transfers his rights to another agent, this transfer is subject to the enterprise delegation policies.in delegation frameworks, authorizing a request requires finding a valid chain of credentials that delegates the authority from the source (the local policy of the entity that serves the request) to the requester. unfortunately, chain discovery is a computationally expensive and time consuming task. it was shown that, in the general case, chain discovery is undecidable, and in more restrictive cases, it is polynomial in the number of credentials available to the server. verifying compliance with the terms of a delegation policy adds a considerable overhead to request authorization.this paper presents a framework that considerably reduces the time required to authorize a request. in this framework, a delegation chain is condensed into a single credential, called chained delegation certificate (cdc). a cdc attests that the owner has a certain right, and serves as proof that every link in the chain complies with the policy governing delegation of the right in question. when cdcs are used for authorization, a server does not need to verify compliance with the delegation policy, nor does it need to perform the chain discovery step, and therefore requests are served considerably faster.
class-dependent assignment in cluster-based servers. a cluster-based server consists of a front-end dispatcher and several back-end servers. the dispatcher receives incoming requests, and then assigns them to back-end servers for processing. our goal is to devise an assignment policy that has good response time performance, and is practical to implement in that the amount of information used by the dispatcher is relatively small, so that the attendant computation and communication overheads are low. in contrast to extant assignment policies that apply the same assignment policy to all incoming jobs, our approach calls for the dispatcher to classify incoming jobs as long or short, and then use class-dependent assignment policies. specifically, we propose a policy, called cda (class dependent assignment), where short jobs are assigned in round-robin manner as soon as they arrive, while long jobs are deferred and assigned only when a back-end server becomes idle. furthermore, when processing a long job, a back-end server is not assigned any other jobs.our approach is motivated by empirical evidence suggesting that the sizes of files traveling on the internet follow power-law distributions, where long jobs constituting a small fraction of all incoming jobs actually account for a large fraction of the overall load. to gauge the performance of the proposed policy, we exercised it on empirical data traces measured at internet sites serving the 1998 world cup. since the assignment of long jobs incurs computational overhead as well as extra communication overhead, we studied the performance of cda as function of the fraction of jobs classified as long. our study shows that classification of even a small fraction of jobs as long can have a profound impact on overall response time performance. more speciafically, our experimental results show that if less than 3% of the jobs are classified as long, then cda outperforms traditional policies, such as round-robin, by two orders of magnitude. from an implementation viewpoint, these results support our contention that cda-based assignment is a practical policy combining low overhead and greatly improved performance.
eronto: a tool for extracting ontologies from extended e/r diagrams. realization of semantic web requires structuring of web data using domain ontologies. most data intensive websites are powered by relational databases whose design process involves developing conceptual model using e/r or extended e/r diagrams. this paper discusses the implementation details of a tool that builds domain ontologies in owl (ontology web language) from extended e/r diagrams. ontology development being a knowledge intensive task, our tool would be helpful in reducing the developmental efforts by automating the process. we bring out the differences and the similarities between the expressive capabilities of the two conceptual modeling methods, namely owl and extended e/r diagrams.