waashk/dblp huggingface dataset:
color patterns for pictorial content description. in this paper, we propose a new type of image feature, which consists of patterns of colors and intensities that capture the latent associations among images and primitive features in such a way that the noise and redundancy are minimized. incorporating our feature model into a content-based image retrieval (cbir) system moves the research in image retrieval beyond simple matching of images based on their primitive features and creates a ground for learning image semantics from visual content. a system developed using our proposed feature model, will have the capability of learning associations between not only semantic concepts and images, but also between semantic concepts and patterns. we evaluated the performance of our system based on the retrieval accuracy and on the perceptual similarity order among retrieved images. when compared to standard image retrieval methods, our preliminary results show that, even if the feature space was reduced to a significantly lower dimensional space, the accuracy and perceptual similarity for our system remain the same or better depending on the category of images.
distributed evaluation of generalized path queries. nowadays, we are required to deal with more complex data, prime examples of which are data on the web, xml data, biological data, etc. there are already proposed abstractions to handle these kinds of data, in particular in terms of semistructured data models. a semistructured model conceives a database essentially as a finite directed labeled graph whose nodes represent objects, and whose edges represent relationships between objects. in this paper, we focus on path queries, which are considered the basic querying mechanism for semistructured data. in essence, such queries are used to navigate, or discover paths that conform to specifications captured by regular expressions. in order to make the navigation more useful, we consider generalized path queries, in which the symbols could optionally be weighted by numbers. such numbers can express a variety of information about the data that the query could possibly match or navigate.motivated by the plethora of today's applications utilizing web services and peer-to-peer architectures, we present a distributed algorithm for evaluating generalized path queries. we follow a realistic model with distributed (non-shared) memory and message-passing between processors. an optimal solution to the problem lies in the intersection of ideas related to distributed query evaluation, distributed shortest path computation, and queueing systems.
metrics for evaluating concern separation and composition. this paper discusses an approach to evaluating the separation of concerns for an object-oriented software system. for assessing this separation, the developer is asked to specify the nature of classes through annotations. automatic identification of some structural characteristics (e.g., inheritance, libraries, synchronisation) is used to appraise the composition and intertwining of concerns inside a class.
enforcing agent communication laws by means of a reflective framework. agent coordination contexts (accs) have been proposed as virtual environments where agents live and interact. in this way, as in a human society, interactions may be subjected to conventions and laws depending on their context. this is obtained by a suitable acc that embeds the communication laws relevant to a specific application and checks whether they are fulfilled as interactions take place.context modelling, while representing a communication aspect relevant for all the agents of an application, is a crosscutting concern with respect to the design of the activities of each agent. in this paper, we propose an approach allowing a separate design and implementation of, respectively, behaviour and the interaction aspects constituting the context. once the latter have been formalised in a specification consisting of communication laws, a tool generates the necessary management and checking code from the specification.moreover, we automate the way laws are enforced on agent communication by suitably redirecting any interaction between agents, so as to ensure that the constraints specified by the laws are respected by the interaction, and the actions required by some laws are taken before it actually takes place. redirection is accomplished by means of computational reflection, which transparently changes the meaning of the communication primitives normally used by agents programmers.
collaborative attack modeling. avoidance and discovery of security vulnerabilities in information systems requires awareness of typical risks and a good understanding of vulnerabilities and their exploitations. in this paper we compare common methods of sharing security related knowledge with regard to their ability to support avoidance and discovery of vulnerabilities. we suggest a new method of collaborative attack modeling that is especially suitable for this purpose. this method combines a graph-based attack modeling technique with ideas of a web-based collaboration tool.
decoupling classes with inferred interfaces. using small, context-specific interfaces in variable declarations serves the decoupling of classes and increases a program's flexibility. to minimize its interface, a thorough analysis of the protocol needed from a variable is required. currently available refactorings for the extraction of interfaces leave the programmer alone with the decision which methods to include or, more problematically, which to omit: they let him choose manually from the protocol of an existing type, and only then offer to use the new interface where (if) possible. to aid the programmer in defining a new interface, we have developed a new refactoring that infers it from a variable's declaration and automatically inserts it into the code.
a lightweight java taskspaces framework for scientific computing on computational grids. a prototype taskspaces framework for grid computing of scientific computing problems that require intertask communication is presented. the taskspaces framework is characterized by three major design choices: decentralization provided by an underlying tuple space concept, enhanced direct communication between tasks by means of a communication tuple space distributed over the worker hosts, and object orientation and platform independence realized by implementation in java. grid administration tasks, for example resetting worker nodes, are performed by mobile agent objects. we report on large-scale grid computing experiments for iterative linear algebra applications showing that our prototype framework scales well for scientific computing problems that require neighbor-neighbor intertask communication. it is shown in a computational fluid dynamics simulation using a lattice boltzmann method that the taskspaces framework can be used naturally in interactive collaboration mode. the scalable taskspaces framework runs fully transparently on heterogeneous grids while maintaining a low complexity in terms of installation, maintenance, application programming and grid operation. it thus offers a promising roadway to push scientific grid computing with intertask communication beyond the experimental research setting.
terascale simulation of cumulus convection on asci white. this talk presents three-dimensional numerical simulations of oceanic trade cumulus clouds underlying stratocumulus clouds. they use a case studied in a global energy and water experiment cloud system study (gcss) model intercomparison that is loosely based on observed conditions during the atlantic trade cumulus experiment (atex). this case study is motivated by the importance of this cloud type to global cloud radiative forcing, and their role as a feeder system for deep convection in the topics. this study focuses on the sensitivity of the modeled cloud field to the domain size and the grid spacing. domain widths from 6.5 to 20 kilometers and horizontal grid spacings ranging from 10 to 80 meters, with corresponding vertical grid spacing ranging from 5 to 40 m, are studied, involving domains with over 1000 gridpoints in each horizontal dimension.the combination of large domain size and small grid resolution (up to 2.5 billion grid-cells) provides an unprecedented perspective on this type of convection. this is in contrast to prior les simulations which have often used domains a few kilometers wide. the larger domain size considered here is comparable to the grid resolution of a typical current mesoscale model (a similar resolution will soon be achieved in some global weather forecast models), and can better represent the potential horizontal variability achievable within a mesoscale grid cell. these simulations are made possible by massively parallel computations using 1.3 terabytes of memory and over 1000 processors.
http redirection for replica catalogue lookups in data grids. data distribution and replication in distributed systems require special purpose middleware tools for accessing replicated data. data grids, special forms of systems distributed over wide-area networks, need to handle data management issues like distribution and replication of large amounts of data in the tera- and petabyte scale. replica catalogues are used for cataloguing and locating replicated files in distributed sites all around the globe. we present a novel and administratively scalable approach for distributing a replica catalogue and resolving file location information by using http redirection. http redirection servers managing local file catalogues allow for greater flexibility and local file management autonomy whereas a global replica catalogue provides the necessary mapping of logical files to individual sites. by distributing the catalogues a site can autonomously move files for load balancing within a site without notifying a global replica catalogue. our approach scales well in terms of catalogue administration to a large number of sites and file entries and thus establishes a powerful middleware service. we present the design and implementation of our catalogue redirection servers and report on promising experimental results.
migrating data-intensive web sites into the semantic web. the semantic web is intended to enable machine processability of web content and seems to be a solution for many drawbacks of the current web. it is based on metadata that describe the formal semantics of web contents. we present a novel, integrated and automated approach for migrating data-intensive web applications into the semantic web. this approach can be applied to a broad range of today's business web sites.
model refactorings through rule-based inconsistency resolution. the goal of model-driven engineering is to raise the level of abstraction by shifting the focus to models. as a result, complex software development activities move to the modelling level as well. one such activity is model refactoring, a technique for restructuring the models in order to improve some quality attributes of the models. as a first contribution of this paper, we argue and show that refactoring a model is enabled by inconsistency detection and resolution. inconsistencies in or between models occur since models typically describe a software system from different viewpoints and on different levels of abstraction. a second contribution of this paper is rule-based inconsistency resolution, which enables reuse of different inconsistency resolutions across model refactorings and manages the flow of inconsistency resolution steps automatically.
efficient diffie-hellmann two-party key agreement protocols based on elliptic curves. key agreement protocols are of fundamental importance for ensuring the confidentiality of communications between two (or more) parties over an insecure network. in this paper we review existing two-party protocols whose security rests upon the intractability of diffie-hellmann and discrete logarithm problems over elliptic curve groups. in addition, we propose a new two-party mutual authenticated key agreement protocol and collectively evaluate the security and performance of all the schemes considered. elliptic curve techniques are used to minimise the computational workload on resource-constrained devices and to afford security levels with possibly fewer bits.
an anonymous bonus point system for mobile commerce based on word-of-mouth recommendation. next generation mobile devices will allow users to share and pass information within anonymous groups of people in an ad hoc manner. this will smooth the path for many kinds of new mobile commerce applications. in this paper we present a mobile commerce application that is part of the iclouds research project. it allows the dissemination of digital advertisements among interested mobile users. to create an incentive, an anonymous bonus point system rewards users who help to carry an advertisement from a merchant to a customer. this work includes a formal description of our bonus point model, a thorough discussion of the security goals, their realization and some first results about crypto-operation runtime behavior on a state-of-the-art pda.
lost in just the translation. this paper describes the design and implementation of a scheme for hiding information in translated natural language text, and presents experimental results using the implemented system. unlike the previous work, which required the presence of both the source and the translation, the protocol presented in this paper requires only the translated text for recovering the hidden message. this is a significant improvement, as transmitting the source text was both wasteful of resources and less secure. the security of the system is now improved not only because the source text is no longer available to the adversary, but also because a broader repertoire of defenses (such as mixing human and machine translation) can now be used.
semantic enrichment for improving systems interoperability. the overall goal addressed in this paper is to improve semantic interoperability in heterogeneous systems by means of establishing mappings between relevant domain ontologies. the mappings are discovered based on the technique of semantic enrichment through extension analysis, i.e. using instance information of the ontology to enrich the original ontology and further to calculate similarities between concepts in two ontologies. text categorization is used to automatically assign instance to the concepts in the ontology. information retrieval techniques are used to calculate similarity between concepts. based on the similarities measure, a heuristic method is used to establish mapping assertions for the two ontologies. the method is illustrated using a product catalogue scenario.
contradictions and critical issues during system evolution. in this paper the issue of system evolution is addressed. activity theory and the concept of exapansive cycles are reviewed as theories to explain systemic evolution. contradictions often manifest themselves in deviating human behaviour or in modifications to external artefacts, i.e., they result in a form of systemic behaviour which has often been treated as undesirable. it is shown that contradictions within activity systems are both catalysts and opportunities for system change. in the context of safety-related systems this is put at the centre of investigation in the form of critical issues. an example from an industrial case study is reported, where this approach was applied, and where with this approach affective and communicational problems were identified.
an approach to acquire semantic relationships between terms. this paper focuses on the automatic acquisition of semantic relationships from chinese corpus, motivated by improving the performances of our qa systems named nl-was. linguistic patterns designed for chinese sentences are applied to a collection of texts to extract synonymy relationship, hyponymy relationship, and meronymy relationship. patterns are broken down into unambiguous and ambiguous, and different strategies are adopted to refine the candidates extracted using this two kinds of patterns. compared to other previous works, we apply not only strict unambiguous patterns but also loose unambiguous patterns to extract relationships and proposed efficient approach to refine the outputs of these patterns for the sake of high recall and high precision. the experimental result shows that the proposed method can delete most noisy pairs of terms and improve accuracy and efficiency of nl-was. at the same time, our method is complementary to statistically based approaches that find semantic relationships between terms.
scalable and lock-free concurrent dictionaries. we present an efficient and practical lock-free implementation of a concurrent dictionary that is suitable for both fully concurrent (large multi-processor) systems as well as pre-emptive (multi-process) systems. many algorithms for concurrent dictionaries are based on mutual exclusion. however, mutual exclusion causes blocking which has several drawbacks and degrades the system's overall performance. non-blocking algorithms avoid blocking, and are either lockfree or wait-free. our algorithm is based on the randomized sequential list structure called skiplist, and implements the full set of operations on a dictionary that is suitable for practical settings. in our performance evaluation we compare our algorithm with the most efficient non-blocking implementation of dictionaries known. the experimental results clearly show that our algorithm outperforms the other lockfree algorithm for dictionaries with realistic sizes, both on fully concurrent as well as pre-emptive systems.
type-safe covariance in c++. we present a programming technique for implementing type safe covariance in c++. in a sense, we implement most of bruce's matching approach to the covariance dilemma in c++. the appeal in our approach is that it relies on existing mechanisms, specifically templates, and does not require any modification to the existing language. the practical value of the technique was demonstrated in its successful incorporation in a large software body. we identify the ingredients of a programming language required for applying the technique, and discuss extensions to other languages.
finding an optimum edit script between an xml document and a dtd. finding an optimum edit script between data plays an important role in data retrieval and data transformation. many methods for finding an optimum edit script between two xml documents have been proposed so far, but few studies on finding an optimum edit script between an xml document and a dtd have been made. in this paper, we first show a polynomial-time algorithm that finds an optimum edit script between an xml document (modeled as an ordered tree) and a dtd. we next prove that, if the cost of an operation on a node in a tree may depend on the other nodes, then the corresponding decision problem becomes strongly np-complete.
mobile delivery of news using hierarchical query-biased summaries. this paper presents the results of a study aimed at measuring the usefulness of presenting the results of an information retrieval search on wap mobile phones. the experimentation focuses on presenting automatically-generated summaries of newspaper articles of increasing length on a mobile phone interface and in studying the differences in users' perception of relevance of the retrieved documents. the aim is to study experimentally how users' perception of relevance varies depending on the length of the summary, and in relation to the specific characteristic of the mobile interface that content is presented. experimental results suggest that hierarchical query biased summaries are useful when dealing with small screens and assist users in making correct relevance judgments.
investigating the use of summarisation for interactive xml retrieval. as the number of components in xml documents is much larger than that of 'flat' documents, we believe it is essential to provide users of xml information retrieval systems with overviews of the content of retrieved elements. in this paper, we investigate the use of summarisation in xml retrieval as a means of helping users in their searching process.
implicit environment-based coordination in pervasive computing. by immersing computational systems into the physical world, pervasive computing brings us from traditional desktop computing interactions into a form closer to human interactions, which are characterized by their dependance on the environment. furthermore, acting within the environment can contribute in many cases to a form of implicit interaction in which no explicit communication message is exchanged. however, this way of interacting cannot be achieved without a shared common knowledge with a well defined semantic. this appeals to explore a new approach of interaction mediated by the environment, closer to human interactions, and therefore, more suitable to achieve the intended silent computation of pervasive computing.to address this issue, we present in this paper xcm; a generic coordination model for pervasive computing. xcm is organized around few abstract concepts (entity, environment, social law and port) and is expressed as an ontology. while the abstract concepts of xcm deal with the environmental representation and context-dependency, the ontological representation allows to achieve knowledge sharing and context reasoning.
email classification for automated service handling. we describe the experience and lessons learned from developing a range of electronic services for a specialist engineering company. we are using a custom workflow management system as the base for a range of services which are offered via a multi-modal portal, using a language-based approach to extracting information from html forms, email, and sms. we describe the email classification experiments we have carried out and discuss the development of customer services based on automatic email classification.
an improvement on binary-swap compositing for sort-last parallel rendering. sort-last parallel rendering is a good rendering scheme on distributed memory multiprocessors. this paper presents an improvement on the binary-swap (bs) method, which is an efficient image compositing algorithm for sort-last parallel rendering. our compositing method uses three acceleration techniques, compared to the original bs method. through the use of the three techniques, our method balances the compositing load among processors, exploits more sparsity of the image, and reduces the cost of communication. we also show some experimental results on a pc cluster. the results show that our method completes the image compositing faster than the original bs method, and its speedup to the original increases with the number of processors.
certificates for mobile code security. the problem of protecting mobile code from malicious hosts is an important security issue, for which many solutions have been proposed. we describe a method to adapt an existing technique, execution tracing, to enhance its flexibility in deployment for a large scale mobile agent system. this is achieved through the introduction of a trusted third party, the verification server, which undertakes the verification of execution traces on behalf of the platform launching the agent. the server constructs a certificate that testifies to the capability of a particular host platform to undertake the correct execution of a mobile agent. in this sense, the server assumes a role analogous of a certificate authority (ca) in a pki. we briefly discuss the issues associated with such a framework.