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Distributed Clone Detection in Static Wireless Sensor Networks: Random Walk with Network Division

Khan, Wazir Zada; Aalsalem, Mohammed Y.; Saad, N. M.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 18/05/2015 Português
Relevância na Pesquisa
47.547383%
Wireless Sensor Networks (WSNs) are vulnerable to clone attacks or node replication attacks as they are deployed in hostile and unattended environments where they are deprived of physical protection, lacking physical tamper-resistance of sensor nodes. As a result, an adversary can easily capture and compromise sensor nodes and after replicating them, he inserts arbitrary number of clones/replicas into the network. If these clones are not efficiently detected, an adversary can be further capable to mount a wide variety of internal attacks which can emasculate the various protocols and sensor applications. Several solutions have been proposed in the literature to address the crucial problem of clone detection, which are not satisfactory as they suffer from some serious drawbacks. In this paper we propose a novel distributed solution called Random Walk with Network Division (RWND) for the detection of node replication attack in static WSNs which is based on claimer-reporter-witness framework and combines a simple random walk with network division. RWND detects clone(s) by following a claimer-reporter-witness framework and a random walk is employed within each area for the selection of witness nodes. Splitting the network into levels and areas makes clone detection more efficient and the high security of witness nodes is ensured with moderate communication and memory overheads. Our simulation results show that RWND outperforms the existing witness node based strategies with moderate communication and memory overheads.

Detection and quantification of Erysiphe necator DNA in wine grapes and resultant must and juice

Stummer, B.; Zanker, T.; Harvey, P.; Scott, E.
Fonte: Cambridge Univ Press Publicador: Cambridge Univ Press
Tipo: Artigo de Revista Científica
Publicado em //2006 Português
Relevância na Pesquisa
37.241943%
Powdery mildew of grapevines is difficult to assess visually at the weighbridge, particularly in large consignments of machine-harvested fruit. To facilitate accurate methods for the detection and quantification of the disease in grape samples obtained from both the vineyard and winery, we developed a DNA probe for the pathogen Erysiphe necator. The E. necator-specific 450 bp DNA fragment pEnA1, targets highly repetitive sequences and was isolated from a partial genomic library. In screening for species specificity, clone pEnA1 was used in slot-blot hybridization and detected E. necator DNA from grapes and resultant must and juice, but not from clarified juice and wine. The detection threshold was approximately 50 pg ofE. necator DNA per 100 ng total DNA of grape sample and was equivalent to 1–5 % of a grape bunch visually affected by powdery mildew. Disease severity, expressed as the percentage of surface area of a bunch with powdery mildew, and E. necator DNA content were highly correlated, r² = 0.955, P < 0.001. The DNA-based hybridization assay has the potential to predict the severity of powdery mildew in grape samples from the vineyard and in must and juice samples at the winery. The DNA sequence of clone pEnA1 was used to design species-specific primers...

Detecção interprocedimental de clones semânticos; Interprocedural semantic clone detection

Albuquerque, Felipe de Alencar
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 08/11/2013 Português
Relevância na Pesquisa
67.298223%
Fragmentos de código duplicado, ou clones, são inseridos em aplicativos por serem uma maneira simples de reúso, dentre outros motivos. Clones são, portanto, comuns em programas. No entanto, a atividade de manutenção pode ficar custosa se o código do programa analisado possuir muitos clones, principalmente os semânticos, os quais podem possuir códigos distintos, mas realizam tarefas similares. Nesse sentido, a utilização de ferramentas que automatizam a tarefa de detectar clones é desejável. Ferramentas atuais de detecção de clones semânticos são capazes de identificar esses clones com altas taxas de acerto. No entanto, elas não são capazes de identificar clones semânticos considerando também os fluxos dos procedimentos ou funções que são invocados dentro dos fragmentos de código comparados. Essa limitação pode levar as ferramentas a indicarem clones semânticos falso positivos. Este trabalho apresenta uma técnica de detecção de clones semânticos que considera as chamadas de procedimentos presentes nos programas. Essa técnica apresentou uma taxa de acertos 2,5% maior do que técnicas convencionais de acordo com um benchmark, também desenvolvido neste trabalho. Esse benchmark foi criado com base nas classificações de clones fornecidas por programadores da indústria e da academia. A técnica interprocedimental de detecção de clones semânticos pode ser utilizada para evolução...

A Mutation Analysis Based Model Clone Detector Evaluation Framework

Stephan, MATTHEW
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
57.806797%
Model-Driven Engineering is becoming increasingly prevalent and mature. As software projects developed through this methodology age, the need for analysis of Model-Driven projects becomes imperative. One form of analysis is Model Clone Detection, which involves finding similar or identical model fragments in a given context. There are a number of techniques intended for Model Clone Detection and for different types of models. One hindrance to the growth of this field is the ability to objectively and quantitatively compare different model clone detectors and settings of the same detector. In this thesis, our original contribution to knowledge includes a framework utilizing Mutation Analysis to evaluate and compare model clone detectors. It is our proposition that, through distinguishing edit operations on models as mutations, we can create such a framework. In order to demonstrate the plausibility of our framework, we develop a Simulink implementation of the framework. We begin by outlining our initial, qualitative, attempts evaluating our Simulink model clone detector. This includes challenges encountered that are addressed by our framework. We outline the framework and describe each step in its process in an example-driven manner through creation of a framework prototype that works on Simulink model clone detectors. We choose Simulink because it is the most mature form of Model Clone Detection...

Towards Web Service Tagging By Similarity Detection

Martin, Douglas
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
47.298223%
The web of the future will require automated tagging of equivalent or similar services in support of service discovery and the selection of appropriate alternatives in case of failure. Code similarity detection tools, or clone detectors, provide a mature and scalable method of identifying these kinds of similarities and can be used to assist in this problem. However, they require a set of units to be compared; something to which the most popular description language, WSDL (Web Service Description Language), does not lend itself. First, each WSDL description can contain more than one operation description, which does not provide the granularity we need to compare services on the operation level. Secondly, these operation descriptions are mixed together throughout the file, often sharing some common elements. This thesis describes a technique for extracting the elements of each operation description and consolidating them into a self-contained unit using TXL, a source transformation language. These units, referred to as Web Service Cells or WSCells (pronounced “wizzles”), can then be used by similarity detectors to search for similarities. We describe a modified architecture to the NICAD clone detector to support the creation of WSCells...

AN EMPIRICAL STUDY FOR THE IMPACT OF MAINTENANCE ACTIVITIES IN CLONE EVOLUTION

MARKS, LIONEL
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1055138 bytes; application/pdf
Português
Relevância na Pesquisa
57.45556%
Code clones are duplicated code fragments that are copied to re-use functionality and speed up development. However, due to the duplicate nature of code clones, inconsistent updates can lead to bugs in the software system. Existing research investigates the inconsistent updates through analysis of the updates to code clones and the bug fixes used to fix the inconsistent updates. We extend the work by investigating other factors that affect clone evolution, such as the number of developers. On two levels of analysis, the method and clone class level, we conduct an empirical study on clone evolution. We analyze the factors affecting bug fixes and co-change (i.e. update cloned methods at the same time) using our new metrics. Our metrics are related to the developers, code complexity, and stages of development. We use these metrics to find ways to improve the maintenance of cloned code. We discover that one way to improve maintenance of code clones is the decrease of code complexity. We find that increased code complexity leads to a decrease in co-change, which can lead to bugs in the software. We perform our study on 6 applications. To maximize the number of clones detected, we use two existing code clone detection tools: SimScan and Simian. SimScan was used to find clones in 5 of the applications due to its versatility in finding code clones. Simian was used to detect clones due to its reliability to find code clones regardless of language or compilation problems. To analyze and determine the significance of the metrics...

BUSINESS PROCESS RECOVERY USING UI DESIGN PATTERNS AND CLONE DETECTION IN BUSINESS PROCESSES

Guo, JIN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1597320 bytes; application/pdf
Português
Relevância na Pesquisa
67.298223%
A business application automates a collection of business processes. A business process describes how a set of logically related tasks are executed, ordered and managed by following business rules to achieve business objectives. An “online book purchase” business process contains several tasks such as buying a book, ordering a book, and sending out promotions. In this ever changing business environment, both of business applications and business processes are modified to accommodate changed business requirements and improve the performance of the organization. These continuous modifications introduce problems in the following two aspects: 1) Business process definitions are rarely updated to reflect the current business processes deployed in business applications. 2) Business processes may be cloned (e.g., copied and slightly modified) to handle special circumstances or promotions. Identifying these clones and removing them help improve the efficiency of an organization. However, business processes are defined with textual languages that cannot be automatically understood. To maintain business process definitions up to date, we present our techniques that automatically recover business processes from UIs of business applications and identify clones in the recovered business processes. We leverage UI design patterns...

Clone Detection In Matlab Stateflow Models

Chen, JIAN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
47.36377%
Matlab Simulink is one of the leading tools for model based software development in the automotive industry. One extension to Simulink is Stateflow, which allows the user to embed Statecharts as components in a Simulink Model. These state machines contain nested states, an action language that describes events, guards, conditions and actions and complex transitions. As Stateflow has become increasingly important in Simulink models for the automotive sector, we extend previous work on clone detection of Simulink models to Stateflow components. In this thesis, we present an approach for identifying Stateflow clones in Matlab Stateflow models. In order to leverage robust near-miss code clone technology, our approach is text-based. First, we transform the Stateflow textual representation into a hierarchical textual structure. We implement a SIMONE plugin that normalizes the initial input to remove irrelevant elements and rename irrelevant naming differences to make the process of clone identification more accurate. Finally, we identify potential clone candidates and cluster them into classes. We conducted experiments with our approach on the Matlab Simulink/Stateflow Demo set. Our approach showed promising results on the identification of Stateflow clones as an isolated component as well as an integrated component of the Simulink models that are hosting them. All of our results are manually validated.; Thesis (Master...

Empirical Studies of Code Clone Genealogies

BARBOUR, LILIANE JEANNE
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
47.422544%
Two identical or similar code fragments form a clone pair. Previous studies have identified cloning as a risky practice. Therefore, a developer needs to be aware of any clone pairs so as to properly propagate any changes between clones. A clone pair experiences many changes during the creation and maintenance of software systems. A change can either maintain or remove the similarity between clones in a clone pair. If a change maintains the similarity between clones, the clone pair is left in a consistent state. However, if a change makes the clones no longer similar, the clone pair is left in an inconsistent state. The set of states and changes experienced by clone pairs over time form an evolution history known as a clone genealogy. In this thesis, we provide a formal definition of clone genealogies, and perform two case studies to examine clone genealogies. In the first study, we examine clone genealogies to identify fault-prone “patterns” of states and changes. We also build prediction models using clone metrics from one snapshot and compare them to models that include historical evolutionary information about code clones. We examine three long-lived software systems and identify clones using Simian and CCFinder clone detection tools. The results show that there is a relationship between the size of the clone and the time interval between changes and fault-proneness of a clone pair. Additionally...

NeCO: Ontology Alignment using Near-miss Clone Detection

Geesaman, Paul Louis
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
67.47501%
The Semantic Web is an endeavour to enhance the web with the ability to represent knowledge. The knowledge is expressed through what are called ontologies. In order to make ontologies useful, it is important to be able to match the knowledge represented in different ontologies. This task is commonly known as ontology alignment. Ontology alignment has been studied, but it remains an open problem with an annual competition dedicated to measure alignment tools' performance. Many alignment tools are computationally heavy, require training, or are useful in a specific field of study. We propose an ontology alignment method, NeCO, that builds on clone detection techniques to align ontologies. NeCO inherits the clone detection features, and it is light-weight, does not require training, and is useful for any ontology.; Thesis (Master, Computing) -- Queen's University, 2014-01-29 14:38:52.873

An Approach to Clone Detection in Behavioral Models

ANTONY, ELIZABETH
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
67.547383%
In this thesis, we present an approach for identifying near-miss interaction clones in reverse-engineered UML behavioural models. Our goal is to identify patterns of interaction ("conversations") that can be used to characterize and abstract the run-time behaviour of web applications and other interactive systems. In order to leverage robust near-miss code clone technology, our approach is text-based, working on the level of XMI, the standard interchange serialization for UML. Behavioural model clone detection presents several challenges - first, it is not clear how to break a continuous stream of interaction between lifelines (lifelines represent the objects or actors in the system) into meaningful conversational units. Second, unlike programming languages, the XMI text representation for UML is highly non-local, using attributes to reference information in the model file remotely. In this work we use a set of contextualizing source transformations on the XMI text representation to reveal the hidden hierarchical structure of the model and granularize behavioural interactions into conversational units. Then we adapt NiCad, a near-miss code clone detection tool, to help us identify conversational clones in reverse-engineered behavioural models. These conversational clones are then analysed to find worrisome patterns of security access violations.; Thesis (Master...

LEVERAGING HISTORICAL CODE CHANGES TO SUPPORT CLONE MANAGEMENT ACTIVITIES

Sourav, SUMIT
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
57.930635%
Code clones are code snippets that come into existence when developers copy paste (and possibly modify) an existing piece of code. Studies show that cloning is an inevitable phenomenon leading to a significant presence of code clones (as much as 10%-30% of the source code consists of cloned code) in large software systems. To effectively manage these clones, researchers have proposed multiple activities along two dimensions: 1) proactive clone management, and 2) post-mortem clone management. Proactive clone management emphasis is on activities that prevent the introduction of new clones into the source code (e.g., identifying the factors that influence developers to clone code). On the other hand, post-mortem clone management focuses on managing the existing clones (e.g., detection or refactoring of a clone). In this thesis, we examine several open issues along both dimensions of clone management activities. For example, over 80% of research focuses on the detection of clones and studying their impact on code quality. However, limited research has examined the factors that make code more likely to be cloned. We find that an increase in the complexity of a method increases the likelihood of code being cloned from that method. Moreover...

Detection and Analysis of \\ Detection and Analysis of Near-Miss Software Clones

Roy, CHANCHAL
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1434286 bytes; application/pdf
Português
Relevância na Pesquisa
57.8227%
Software clones are considered harmful in software maintenance and evolution. However, despite a decade of active research, there is a marked lack of work in the detection and analysis of near-miss software clones, those where minor to extensive modifications have been made to the copied fragments. In this thesis, we advance the state-of-the-art in clone detection and analysis in several ways. First, we develop a hybrid clone detection method, called NICAD, that can detect both exact and near-miss clones with high precision and recall and with reasonable performance. Second, in order to address the decade of vagueness in clone definition, we propose an editing taxonomy for clone creation that models developers' editing activities in the copy/pasted code in a top-down fashion. NICAD is designed to address the different types of clones in the editing taxonomy. Third, we have conducted a scenario-based qualitative comparison and evaluation of all of the currently available clone detection techniques and tools in the context of a unified conceptual framework. Using the results of this study one can more easily choose the right tools to meet the requirements and constraints of any particular application, and can identify opportunities for hybridizing different techniques. The hybrid architecture of NICAD was derived from this study. Fourth...

Detection and Analysis of \\ Detection and Analysis of Near-Miss Software Clones

Roy, CHANCHAL
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 1434286 bytes; application/pdf
Português
Relevância na Pesquisa
57.8227%
Software clones are considered harmful in software maintenance and evolution. However, despite a decade of active research, there is a marked lack of work in the detection and analysis of near-miss software clones, those where minor to extensive modifications have been made to the copied fragments. In this thesis, we advance the state-of-the-art in clone detection and analysis in several ways. First, we develop a hybrid clone detection method, called NICAD, that can detect both exact and near-miss clones with high precision and recall and with reasonable performance. Second, in order to address the decade of vagueness in clone definition, we propose an editing taxonomy for clone creation that models developers' editing activities in the copy/pasted code in a top-down fashion. NICAD is designed to address the different types of clones in the editing taxonomy. Third, we have conducted a scenario-based qualitative comparison and evaluation of all of the currently available clone detection techniques and tools in the context of a unified conceptual framework. Using the results of this study one can more easily choose the right tools to meet the requirements and constraints of any particular application, and can identify opportunities for hybridizing different techniques. The hybrid architecture of NICAD was derived from this study. Fourth...

DETECTING PDF JAVASCRIPT MALWARE USING CLONE DETECTION

Karademir, SARUHAN
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
57.547383%
One common vector of malware is JavaScript in Adobe Acrobat (PDF) files. In this thesis, we investigate using near-miss clone detectors to find this malware. We start by collecting a set of PDF files containing JavaScript malware and a set with clean JavaScript from the VirusTotal repository. We use the NiCad clone detector to find the classes of clones in a small subset of the malicious PDF files. We evaluate how clone classes can be used to find similar malicious files in the rest of the malicious collection while avoiding files in the benign collection. Our results show that a 10% subset training set produced 75% detection of previously known malware with 0% false positives. We also used the NiCad as a pattern matcher for reflexive calls common in JavaScript malware. Our results show a 57% detection of malicious collection with no false positives. When the two experiments’ results are combined, the total coverage of malware rises to 85% and maintains 100% precision. The results are heavily affected by the third-party PDF to JavaScript extractor used. When only successfully extracted PDFs are considered, recall increases to 99% and precision remains at 100%.; Thesis (Master, Electrical & Computer Engineering) -- Queen's University...

Pattern Analysis of TXL Programs

Rahman, ASHIQUR
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
Português
Relevância na Pesquisa
47.405063%
All programming languages need to be updated regularly by adding new features that fill programming needs. Existing approaches to determine new language features are completely manual and are based on language developers' experience, source code analysis, feature requests, and programmer interviews. Although these are acceptable practises, they are time-consuming and require a lot of brainstorming tasks, such as preparing interview questions, understanding ambiguous ideas, finding the common requirements, etc. No research, to our knowledge, has attempted to make the task of language feature identification easier. Through our research, we propose a systematic approach for identifying language features with the help of pattern and clone detection tools that work on source code. It semi-automates the task of feature identification, works quickly, and reduces the effort involved in existing practises. We identify features for the TXL language by implementing our idea and enabling the NiCAD clone detector to perform clone analysis on TXL source code, and developing a pattern detector. After detecting code patterns with the pattern detector and analyzing them, we propose eleven new features that can help improve the feature set of TXL.; Thesis (Master...

Detection of Node Clones in Wireless Sensor Network Using Detection Protocols

George, Neenu; Parani, T. K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/03/2014 Português
Relevância na Pesquisa
37.241943%
Wireless sensor networks consist of hundreds to thousands of sensor nodes and are widely used in civilian and security applications. One of the serious physical attacks faced by the wireless sensor network is node clone attack. Thus two node clone detection protocols are introduced via distributed hash table and randomly directed exploration to detect node clones. The former is based on a hash table value which is already distributed and provides key based facilities like checking and caching to detect node clones. The later one is using probabilistic directed forwarding technique and border determination. The simulation results for storage consumption, communication cost and detection probability is done using NS2 and obtained randomly directed exploration is the best one having low communication cost and storage consumption and has good detection probability. Keywords: wireless sensor networks (wsn), distributed hash table, randomly directed exploration.; Comment: 6 pages,5 figures,"Published with International Journal of Engineering Trends and Technology (IJETT)"Volume8 Number 6-Feb2014

Smelling out Code Clones: Clone Detection Tool Evaluation and Corresponding Challenges

Gauci, Rachel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 02/03/2015 Português
Relevância na Pesquisa
47.368174%
Software clones have been an active area of research for the past two decades. However, although numerous clone detection tools are now available, only a small fraction of the literature has focused on tool evaluation, and this is in fact still an open problem. This is mostly due to the fact that standard information retrieval metrics such as recall and precision require a priori knowledge of clones already in the system. Detection tools also typically have a large number of parameters which are difficult to fine-tune for optimal performance on a particular software system, and different outputs produced by different tools add to the complexity of comparing one tool to another. In this review, we further explore the reasons why tool evaluation is still an open challenge, and present the current tools and frameworks targeted at mitigating these problems, focusing on the current standard benchmarks used to evaluate modern clone detection tools, and also presenting a recent method aimed at finding optimal tool configurations.; Comment: 8 pages, 2 figures

An Extended Stable Marriage Problem Algorithm for Clone Detection

AlHakami, Hosam; Chen, Feng; Janicke, Helge
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 13/08/2014 Português
Relevância na Pesquisa
47.12461%
Code cloning negatively affects industrial software and threatens intellectual property. This paper presents a novel approach to detecting cloned software by using a bijective matching technique. The proposed approach focuses on increasing the range of similarity measures and thus enhancing the precision of the detection. This is achieved by extending a well-known stable-marriage problem (SMP) and demonstrating how matches between code fragments of different files can be expressed. A prototype of the proposed approach is provided using a proper scenario, which shows a noticeable improvement in several features of clone detection such as scalability and accuracy.; Comment: 20 pages, 10 figures, 6 tables

Comprehensive clone screening and evaluation of fed-batch strategies in a microbioreactor and lab scale stirred tank bioreactor system : application on Pichia pastoris producing Rhizopus oryzae lipase

Hemmerich, Johannes; Adelantado Vallve, Nuria; Barrigón de San Marcos, José; Ponte, Xavier; Hörmann, Astrid; Ferrer Alegre, Pau; Kensy, Frank; Valero Barranco, Francisco
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2014 Português
Relevância na Pesquisa
37.29436%
Background: In Pichia pastoris bioprocess engineering, classic approaches for clone selection and bioprocess optimization at small/micro scale using the promoter of the alcohol oxidase 1 gene (PAOX1), induced by methanol, present low reproducibility leading to high time and resource consumption. - Results: An automated microfermentation platform (RoboLector) was successfully tested to overcome the chronic problems of clone selection and optimization of fed-batch strategies. Different clones from Mut+P. pastoris phenotype strains expressing heterologous Rhizopus oryzae lipase (ROL), including a subset also overexpressing the transcription factor HAC1, were tested to select the most promising clones. The RoboLector showed high performance for the selection and optimization of cultivation media with minimal cost and time. Syn6 medium was better than conventional YNB medium in terms of production of heterologous protein. The RoboLector microbioreactor was also tested for different fed-batch strategies with three clones producing different lipase levels. Two mixed substrates fed-batch strategies were evaluated. The first strategy was the enzymatic release of glucose from a soluble glucose polymer by a glucosidase, and methanol addition every 24 hours. The second strategy used glycerol as co-substrate jointly with methanol at two different feeding rates. The implementation of these simple fed-batch strategies increased the levels of lipolytic activity 80-fold compared to classical batch strategies used in clone selection. Thus...