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Two interfaces to the RSTM transactional memory system

Eisenstat, David
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Tese de Doutorado Formato: Number of Pages:12 leaves
Português
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Thesis (B.S.)--University of Rochester. Dept. of Computer Science, 2006.; Software transactional memory is a promising new paradigm for concurrent programming. We explore the design of the application programmer interface to RSTM [MSH+06] and propose language extensions to C++ that alleviate some of the unavoidable difficulties with the API.

Natural Language, Knowledge Representation, and Logical Form

Allen, James F.
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
Português
Relevância na Pesquisa
574.9725%
Current natural language understanding systems generaUy maintain a strict division between the parsing processes and the representation that supports general reasoning about the world. This paper examines why these two forms of processing are separated, determines the current advantages and limitations of this approach, and identifies the inherent limitations of the approach. I will point out some fundamental problems with the models as they are defined today and suggest some important directions of research in natural language and knowledge representation. In particular, I will argue that one of the crucial issues facing future natural language systems is the development of knowledge representation formalisms that can effectively handle ambiguity.

L-Fuzzy Structured Query Language

Adjei, Evans
Fonte: Brock University Publicador: Brock University
Tipo: Electronic Thesis or Dissertation
Português
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575.9704%
Lattice valued fuzziness is more general than crispness or fuzziness based on the unit interval. In this work, we present a query language for a lattice based fuzzy database. We define a Lattice Fuzzy Structured Query Language (LFSQL) taking its membership values from an arbitrary lattice L. LFSQL can handle, manage and represent crisp values, linear ordered membership degrees and also allows membership degrees from lattices with non-comparable values. This gives richer membership degrees, and hence makes LFSQL more flexible than FSQL or SQL. In order to handle vagueness or imprecise information, every entry into an L-fuzzy database is an L-fuzzy set instead of crisp values. All of this makes LFSQL an ideal query language to handle imprecise data where some factors are non-comparable. After defining the syntax of the language formally, we provide its semantics using L-fuzzy sets and relations. The semantics can be used in future work to investigate concepts such as functional dependencies. Last but not least, we present a parser for LFSQL implemented in Haskell.

Análisis temporal de una base de datos de preguntas de autoevaluación para el aprendizaje de un lenguaje de programación; Temporal analysis of a self-assesment question database for a programming language learning

García Beltrán, Angel; Martínez, Raquel; Jaén, José Alberto; Tapia, Santiago; Arranz, José María
Fonte: Universidade de Múrcia Publicador: Universidade de Múrcia
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
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The AulaWeb platform has being employed as a learning-teaching support system in the Computer Science course of the Industrial Engineering and Chemical Engineering degrees at the ETSII-UPM since 2000-01 academic year. The self-assessment module is one of the most used functionalities, especially in courses with many enrolled students. The system is used as continuous assessment as the academic lectures take place during the course. This activity mark is taken into account to calculate the corresponding course final mark. The self-assessment module is completed with a database of more than 800 questions. The questions database remains constant since 2004-05 course. In this work, the evolution of self-assessment results is analysed in order to detect a possible system efficiency decrease.; La plataforma AulaWeb lleva empleándose desde el curso 2000-01 como sistema de apoyo docente en la asignatura de Informática del Plan de Estudios de las titulaciones de Ingeniería Industrial e Ingeniería Química en la ETSII-UPM. Una de las funcionalidades más empleadas como recurso de aprendizaje-enseñanza es el módulo de autoevaluación, que se muestra imprescindible en asignaturas como ésta con un elevado número de alumnos matriculados. El sistema se emplea como evaluación continua conforme se avanza durante el periodo académico en la impartición de contenidos en las clases teóricas presenciales. El resultado de la actividad se considera en el cálculo de la calificación final de la asignatura. El módulo de evaluación se alimenta de una base de datos de más de 800 preguntas de diferentes tipos que ha permanecido invariable desde el curso 2004-05. En este trabajo se analiza la evolución de los resultados de la evaluación desde su implantación y la posible disminución de efectividad del sistema

Algebraic Functions, Computer Programming, and the Challenge of Transfer

Schanzer, Emmanuel Tanenbaum
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation; text Formato: application/pdf
Português
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575.00453%
Students' struggles with algebra are well documented. Prior to the introduction of functions, mathematics is typically focused on applying a set of arithmetic operations to compute an answer. The introduction of functions, however, marks the point at which mathematics begins to focus on building up abstractions as a way to solve complex problems. A common refrain about word problems is that “the equations are easy to solve - the hard part is setting them up!” A student of algebra is asked to identify functional relationships in the world around them - to set up the equations that describe a system- and to reason about these relationships. Functions, in essence, mark the shift from computing answers to solving problems. Researchers have called for this shift to accompany a change in pedagogy, and have looked to computer programming and game design as a means to combine mathematical rigor with creative inquiry. Many studies have explored the impact of teaching students to program, with the goal of having them transfer what they have learned back into traditional mathematics. While some of these studies have shown positive outcomes for concepts like geometry and fractions, transfer between programming and algebra has remained elusive. The literature identifies a number of conditions that must be met to facilitate transfer...

The Open Service Compendium. Business-pertinent Cloud Service Discovery, Assessment, and Selection

Slawik, Mathias; Zilci, Begüm İlke; Knaack, Fabian; Küpper, Axel
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/08/2015 Português
Relevância na Pesquisa
574.9892%
When trying to discover, assess, and select cloud services, companies face many challenges, such as fast-moving markets, vast numbers of offerings, and highly ambiguous selection criteria. This publication presents the Open Service Compendium (OSC), an information system which supports businesses in their discovery, assessment and cloud service selection by offering a simple dynamic service description language, business-pertinent vocabularies, as well as matchmaking functionality. It contributes to the state of the art by offering a more practical, mature, simple, and usable approach than related works.; Comment: 14 pages, to be presented at GECON 2015

Privacy by Design: On the Conformance Between Protocols and Architectures

Ta, Vinh-Thong; Antignac, Thibaud
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/01/2015 Português
Relevância na Pesquisa
574.9892%
In systems design, we generally distinguish the architecture and the protocol levels. In the context of privacy by design, in the first case, we talk about privacy architectures, which define the privacy goals and the main features of the system at high level. In the latter case, we consider the underlying concrete protocols and privacy enhancing technologies that implement the architectures. In this paper, we address the question that whether a given protocol conforms to a privacy architecture and provide the answer based on formal methods. We propose a process algebra variant to define protocols and reason about privacy properties, as well as a mapping procedure from protocols to architectures that are defined in a high-level architecture language.; Comment: FPS - 7th International Symposium on Foundations \& Practice of Security, Nov 2014, Montreal, Canada. Springer

Scraping and Clustering Techniques for the Characterization of Linkedin Profiles

Dai, Kais; Nespereira, Celia Gónzalez; Vilas, Ana Fernández; Redondo, Rebeca P. Díaz
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/05/2015 Português
Relevância na Pesquisa
574.9892%
The socialization of the web has undertaken a new dimension after the emergence of the Online Social Networks (OSN) concept. The fact that each Internet user becomes a potential content creator entails managing a big amount of data. This paper explores the most popular professional OSN: LinkedIn. A scraping technique was implemented to get around 5 Million public profiles. The application of natural language processing techniques (NLP) to classify the educational background and to cluster the professional background of the collected profiles led us to provide some insights about this OSN's users and to evaluate the relationships between educational degrees and professional careers.; Comment: In proceedings of the Fourth International Conference on Information Technology Convergence and Services (ITCS 2015), pp. 1-15, January 2015, Zurich(Switzerland)

Functional Programming and Security

Motara, Yusuf Moosa
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 27/01/2012 Português
Relevância na Pesquisa
574.2525%
This paper analyses the security contribution of typical functional-language features by examining them in the light of accepted information security principles. Imperative and functional code are compared to illustrate various cases. In conclusion, there may be an excellent case for the use of functional languages on the grounds of better security; however, empirical research should be done to validate this possibility.

Hyperset Approach to Semi-structured Databases and the Experimental Implementation of the Query Language Delta

Molyneux, Richard
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/02/2009 Português
Relevância na Pesquisa
574.9725%
This thesis presents practical suggestions towards the implementation of the hyperset approach to semi-structured databases and the associated query language Delta. This work can be characterised as part of a top-down approach to semi-structured databases, from theory to practice. The main original part of this work consisted in implementation of the hyperset Delta query language to semi-structured databases, including worked example queries. In fact, the goal was to demonstrate the practical details of this approach and language. The required development of an extended, practical version of the language based on the existing theoretical version, and the corresponding operational semantics. Here we present detailed description of the most essential steps of the implementation. Another crucial problem for this approach was to demonstrate how to deal in reality with the concept of the equality relation between (hyper)sets, which is computationally realised by the bisimulation relation. In fact, this expensive procedure, especially in the case of distributed semi-structured data, required some additional theoretical considerations and practical suggestions for efficient implementation. To this end the 'local/global' strategy for computing the bisimulation relation over distributed semi-structured data was developed and its efficiency was experimentally confirmed.; Comment: Technical Report (PhD thesis)...

A Survey of Quantum Programming Languages: History, Methods, and Tools

Sofge, Donald A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/04/2008 Português
Relevância na Pesquisa
575.82273%
Quantum computer programming is emerging as a new subject domain from multidisciplinary research in quantum computing, computer science, mathematics (especially quantum logic, lambda calculi, and linear logic), and engineering attempts to build the first non-trivial quantum computer. This paper briefly surveys the history, methods, and proposed tools for programming quantum computers circa late 2007. It is intended to provide an extensive but non-exhaustive look at work leading up to the current state-of-the-art in quantum computer programming. Further, it is an attempt to analyze the needed programming tools for quantum programmers, to use this analysis to predict the direction in which the field is moving, and to make recommendations for further development of quantum programming language tools.; Comment: 6 pages

Development of a Window Based Security System for Electronic Data Interchange

Philip, Achimugu; Oluwatolani, Oluwagbemi; Joshua, Abah
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 04/08/2011 Português
Relevância na Pesquisa
574.87617%
The Electronic Data Interchange (EDI) is the exchange of standardized documents between computer systems for business use. The objective of this study is to make Electronic Data Interchange secure to use and to eliminate human intervention in the transfer of data between business partners so that productivity and efficiency can be improved and also promote its usage between two or more trading organizations. This paper provides an overview of EDI by describing the traditional problems of exchanging information in business environments and how the EDI solves those problems and gives benefits to the company that makes use of EDI. This paper also introduces the common EDI Standards and explains how it works, how it is used over the internet and the security measures implemented. The system was executed on both local area network and wide area network after a critical study of the existing EDI methods and also implemented using VB.Net programming language. Finally, an interactive program was developed that handles the transfer of files, with special attention to the security of the items that are being transferred from one computer workstation to another.; Comment: Submitted to Journal of Computer Science and Engineering, see http://sites.google.com/site/jcseuk/volume-7-issue-2-june-2011

Neutral evolution: A null model for language dynamics

Blythe, R. A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/08/2011 Português
Relevância na Pesquisa
575.67996%
We review the task of aligning simple models for language dynamics with relevant empirical data, motivated by the fact that this is rarely attempted in practice despite an abundance of abstract models. We propose that one way to meet this challenge is through the careful construction of null models. We argue in particular that rejection of a null model must have important consequences for theories about language dynamics if modelling is truly to be worthwhile. Our main claim is that the stochastic process of neutral evolution (also known as genetic drift or random copying) is a viable null model for language dynamics. We survey empirical evidence in favour and against neutral evolution as a mechanism behind historical language changes, highlighting the theoretical implications in each case.; Comment: 20 pages, 2 figures. To appear in a special issue of ACS - Advances in Complex Systems on language dynamics

On Probabilistic Parallel Programs with Process Creation and Synchronisation

Kiefer, Stefan; Wojtczak, Dominik
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/12/2010 Português
Relevância na Pesquisa
575.1964%
We initiate the study of probabilistic parallel programs with dynamic process creation and synchronisation. To this end, we introduce probabilistic split-join systems (pSJSs), a model for parallel programs, generalising both probabilistic pushdown systems (a model for sequential probabilistic procedural programs which is equivalent to recursive Markov chains) and stochastic branching processes (a classical mathematical model with applications in various areas such as biology, physics, and language processing). Our pSJS model allows for a possibly recursive spawning of parallel processes; the spawned processes can synchronise and return values. We study the basic performance measures of pSJSs, especially the distribution and expectation of space, work and time. Our results extend and improve previously known results on the subsumed models. We also show how to do performance analysis in practice, and present two case studies illustrating the modelling power of pSJSs.; Comment: This is a technical report accompanying a TACAS'11 paper

Applying convex layers, nearest neighbor and triangle inequality to the Traveling Salesman Problem (TSP)

Liew, Sing
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/04/2012 Português
Relevância na Pesquisa
575.9206%
The author would like to propose a simple but yet effective method, convex layers, nearest neighbor and triangle inequality, to approach the Traveling Salesman Problem (TSP). No computer is needed in this method. This method is designed for plain folks who faced the TSP everyday but do not have the sophisticated knowledge of computer science, programming language or applied mathematics. The author also hopes that it would give some insights to researchers who are interested in the TSP.

A Graphical Adversarial Risk Analysis Model for Oil and Gas Drilling Cybersecurity

Vieira, Aitor Couce; Houmb, Siv Hilde; Insua, David Rios
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/04/2014 Português
Relevância na Pesquisa
574.8818%
Oil and gas drilling is based, increasingly, on operational technology, whose cybersecurity is complicated by several challenges. We propose a graphical model for cybersecurity risk assessment based on Adversarial Risk Analysis to face those challenges. We also provide an example of the model in the context of an offshore drilling rig. The proposed model provides a more formal and comprehensive analysis of risks, still using the standard business language based on decisions, risks, and value.; Comment: In Proceedings GraMSec 2014, arXiv:1404.1634

Modeling the emergence of a new language: Naming Game with hybridization

Pucci, L.; Gravino, P.; Servedio, V. D. P.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
574.8304%
In recent times, the research field of language dynamics has focused on the investigation of language evolution, dividing the work in three evolutive steps, according to the level of complexity: lexicon, categories and grammar. The Naming Game is a simple model capable of accounting for the emergence of a lexicon, intended as the set of words through which objects are named. We introduce a stochastic modification of the Naming Game model with the aim of characterizing the emergence of a new language as the result of the interaction of agents. We fix the initial phase by splitting the population in two sets speaking either language A or B. Whenever the result of the interaction of two individuals results in an agent able to speak both A and B, we introduce a finite probability that this state turns into a new idiom C, so to mimic a sort of hybridization process. We study the system in the space of parameters defining the interaction, and show that the proposed model displays a rich variety of behaviours, despite the simple mean field topology of interactions.; Comment: 12 pages, 10 figures, presented at IWSOS 2013 Palma de Mallorca, the final publication will be available at LNCS http://www.springer.com/lncs

Convergence Time Evaluation of Algorithms in MANETs

Patil, Annapurna P; Sambaturu, Narmada; Chunhaviriyakul, Krittaya
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/10/2009 Português
Relevância na Pesquisa
574.9892%
Since the advent of wireless communication, the need for mobile ad hoc networks has been growing exponentially. This has opened up a Pandoras Box of algorithms for dealing with mobile ad hoc networks, or MANETs, as they are generally referred to. Most attempts made at evaluating these algorithms so far have focused on parameters such as throughput, packet delivery ratio, overhead etc. An analysis of the convergence times of these algorithms is still an open issue. The work carried out fills this gap by evaluating the algorithms on the basis of convergence time. Algorithms for MANETs can be classified into three categories: reactive, proactive, and hybrid protocols. In this project, we compare the convergence times of representative algorithms in each category, namely Ad hoc On Demand Distance Vector (AODV) reactive, Destination Sequence Distance Vector protocol (DSDV) proactive, and Temporally Ordered Routing Algorithm (TORA) hybrid. The algorithm performances are compared by simulating them in ns2. Tcl is used to conduct the simulations, while perl is used to extract data from the simulation output and calculate convergence time. The design of the experiments carried on is documented using Unified modeling Language. Also, a user interface is created using perl...

Facebook and the Epistemic Logic of Friendship

Seligman, Jeremy; Liu, Fenrong; Girard, Patrick
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 23/10/2013 Português
Relevância na Pesquisa
574.9892%
This paper presents a two-dimensional modal logic for reasoning about the changing patterns of knowledge and social relationships in networks organised on the basis of a symmetric 'friendship' relation, providing a precise language for exploring 'logic in the community' [11]. Agents are placed in the model, allowing us to express such indexical facts as 'I am your friend' and 'You, my friends, are in danger'. The technical framework for this work is general dynamic dynamic logic (GDDL) [4], which provides a general method for extending modal logics with dynamic operators for reasoning about a wide range of model-transformations, starting with those definable in propositional dynamic logic (PDL) and extended to allow for the more subtle operators involved in, for example, private communication, as represented in dynamic epistemic logic (DEL) and related systems. We provide a hands-on introduction to GDDL, introducing elements of the formalism as we go, but leave the reader to consult [4] for technical details. Instead, the purpose of this paper is to investigate a number of conceptual issues that arise when considering communication between agents in such networks, both from one agent to another, and broadcasts to socially-defined groups of agents...

MARFCAT: Transitioning to Binary and Larger Data Sets of SATE IV

Mokhov, Serguei A.; Paquet, Joey; Debbabi, Mourad; Sun, Yankui
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
575.1964%
We present a second iteration of a machine learning approach to static code analysis and fingerprinting for weaknesses related to security, software engineering, and others using the open-source MARF framework and the MARFCAT application based on it for the NIST's SATE IV static analysis tool exposition workshop's data sets that include additional test cases, including new large synthetic cases. To aid detection of weak or vulnerable code, including source or binary on different platforms the machine learning approach proved to be fast and accurate to for such tasks where other tools are either much slower or have much smaller recall of known vulnerabilities. We use signal and NLP processing techniques in our approach to accomplish the identification and classification tasks. MARFCAT's design from the beginning in 2010 made is independent of the language being analyzed, source code, bytecode, or binary. In this follow up work with explore some preliminary results in this area. We evaluated also additional algorithms that were used to process the data.; Comment: A shorter version submitted for review to 13th IEEE International Working Conference on Source Code Analysis and Manipulation. 39 pages with figures, tables, TOC, and index