A melhor ferramenta para a sua pesquisa, trabalho e TCC!
Página 1 dos resultados de 5122 itens digitais encontrados em 0.073 segundos
‣ Enhancement of catalog processing system for MIT Science Fiction Society
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 51 leaves; 2047023 bytes; 2046783 bytes; application/pdf; application/pdf
Português
Relevância na Pesquisa
774.8759%
#MIT Science Fiction Society.#Electrical Engineering and Computer Science#Information storage and retrieval systems#Punched card systems#Cataloging Data processing#Libraries Automation#MULTICS (Electronic computer system)
by Cheryl Ann Wheeler.; Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING; Includes bibliographical references.
Link permanente para citações:
‣ SafeJava : a unified type system for safe programming; Unified type system for safe programming
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 164 p.; 8038595 bytes; 8038403 bytes; application/pdf; application/pdf
Português
Relevância na Pesquisa
665.8124%
Making software reliable is one of the most important technological challenges facing our society today. This thesis presents a new type system that addresses this problem by statically preventing several important classes of programming errors. If a program type checks, we guarantee at compile time that the program does not contain any of those errors. We designed our type system in the context of a Java-like object-oriented language; we call the resulting system SafeJava. The SafeJava type system offers significant software engineering benefits. Specifically, it provides a statically enforceable way of specifying object encapsulation and enables local reasoning about program correctness; it combines effects clauses with encapsulation to enable modular checking of methods in the presence of subtyping; it statically prevents data races and deadlocks in multithreaded programs, which are known to be some of the most difficult programming errors to detect, reproduce, and eliminate; it enables software upgrades in persistent object stores to be defined modularly and implemented efficiently; it statically ensures memory safety in programs that manage their own memory using regions; and it also statically ensures that real-time threads in real-time programs are not interrupted for unbounded amounts of time because of garbage collection pauses. Moreover...
Link permanente para citações:
‣ Improving system dynamics teaching using online surveys and exercises
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 67 leaves
Português
Relevância na Pesquisa
765.7392%
As the world becomes increasingly connected, traditional problem solving and decision-making skills becomes less effective. Complex systems found in nature and society exhibit long time delays between cause and effect, feedback, and non-linearity making it difficult to reason effectively about system behavior. Recent studies have shown even highly educated graduate students lack basic systems thinking skills indicating a need for improved system dynamics education. This paper describes the development of a two new tools for improving system dynamics education: a stock-flow simulator that allows users to experiment with simple stock-flow systems, and a web application framework for building system dynamics surveys. This framework is used to build a survey capable of evaluating systems thinking skills and compare the effectiveness of online teaching methods.; by Nicholas A. Behrens.; Thesis (M. Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.; Includes bibliographical references (leaf 50).
Link permanente para citações:
‣ Modeling proteins, making scientists : an ethnography of pedagogy and visual cultures in contemporary structural biology; Ethnography of pedagogy and visual cultures in contemporary structural biology
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 277 p.
Português
Relevância na Pesquisa
1069.329%
This ethnography tracks visualization and pedagogy in the burgeoning field of structural biology. Structural biologists are a multidisciplinary group of researchers who produce models and animations of protein molecules using three-dimensional interactive computer graphics. As they ramp up the pace of structure determination, modeling a vast array of proteins, these researchers are shifting life science research agendas from decoding genetic sequence data to interpreting the multidimensional forms of molecular life. One major hurdle they face is training a new generation of scientists to work with multi-dimensional data forms. In this study I document the formation and propagation of tacit knowledge in structural biology laboratories, in classrooms, and at conferences. This research shows that structural biologists-in-training must cultivate a feel for proteins in order to visualize and interpret their activity in cells. I find that protein modeling relies heavily on a set of practices I call the body-work of modeling. These tacit skills include: a) forms of kinesthetic knowledge that structural biologists gain through building and manipulating molecular models, and by using their own bodies as mimetic models to help them figure out how proteins move and interact; and b) narrative strategies that assume a teleological relationship between form and function...
Link permanente para citações:
‣ Bodies of information : reinventing bodies and practice in medical education; Reinventing bodies and practice in medical education
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 253 p.
Português
Relevância na Pesquisa
1067.7966%
This dissertation recounts the development of graphic models of human bodies and virtual reality simulators for teaching anatomy and surgery to medical students, residents, and physicians. It considers how researchers from disciplinary cultures in medicine, engineering, and computer programming come together to build these technologies, bringing with them values and assumptions about bodies from each of their disciplines, values and assumptions that must be negotiated and that often are made material and embedded in these new technologies. It discusses how the technological objects being created privilege the body as a dynamic and interactive system, in contrast to the description and taxonomic body of traditional anatomy and medicine. It describes the ways that these technologies create new sensory means of knowing bodies. And it discusses the larger cultural values that these technologies reify or challenge. The methodology of this dissertation is ethnography. I consider in-depth one laboratory at a major medical school, as well as other laboratories and researchers in the field of virtual medicine. I study actors in the emerging field of virtual medicine as they work in laboratories, at conferences, and in collaborations with one another. I consider the social formations that are developing with this new discipline. Methods include participant observation of laboratory activities...
Link permanente para citações:
‣ STS.003 The Rise of Modern Science, Spring 2005; The Rise of Modern Science
Fonte: MIT - Massachusetts Institute of Technology
Publicador: MIT - Massachusetts Institute of Technology
Português
Relevância na Pesquisa
676.3369%
#Science#technology#society#modern#seventeenth century#present#Europe#United States#practice#discoveries#progress
This course will study the development of modern science from the seventeenth century to the present, focusing on Europe and the United States. It will not focus on discoveries and their discoverers. Instead, it will examine: What is science? How has science been practiced, and by whom? How are discoveries made and accepted? What is the nature of scientific progress? What is the impact of science and society? What is the impact of society on science? Topics will be drawn from the histories of physics, chemistry, biology, geology, medicine, psychology, and computer science.
Link permanente para citações:
‣ Social media analytics in business intelligence applications
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 93 p.
Português
Relevância na Pesquisa
665.7392%
Social media is becoming increasingly important in society and culture, empowering consumers to group together on common interests and share opinions through the Internet. The social web shifts the originators of content from companies to users. Differences caused by this dynamic result in existing web analytic techniques being inadequate. Because people reveal their thoughts and preferences in social media, there are significant opportunities in business intelligence by analyzing social media. These opportunities include brand monitoring; trend recognition, and targeted advertising. The market for social media analytics in business intelligence is further validated by its direct application in the consumer research market. Challenges lie ahead for development and adoption of social media analytics. Technology used in these analytics, such as natural language processing and social network analysis, need to mature to improve accuracy, performance, and scalability. Nevertheless, social media continues to grow at a rapid pace, and organizations should form strategies to incorporate social media analytics into their business intelligence frameworks.; by Bobby Lo.; Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science...
Link permanente para citações:
‣ A theory and toolkit for the mathematics of privacy : methods for anonymizing data while minimizing information loss
Fonte: Massachusetts Institute of Technology
Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado
Formato: 86 leaves; 14904672 bytes; 14904307 bytes; application/pdf; application/pdf
Português
Relevância na Pesquisa
765.8903%
Privacy laws are an important facet of our society. But they can also serve as formidable barriers to medical research. The same laws that prevent casual disclosure of medical data have also made it difficult for researchers to access the information they need to conduct research into the causes of disease. But it is possible to overcome some of these legal barriers through technology. The US law known as HIPAA, for example, allows medical records to be released to researchers without patient consent if the records are provably anonymized prior to their disclosure. It is not enough for records to be seemingly anonymous. For example, one researcher estimates that 87.1% of the US population can be uniquely identified by the combination of their zip, gender, and date of birth - fields that most people would consider anonymous. One promising technique for provably anonymizing records is called k-anonymity. It modifies each record so that it matches k other individuals in a population - where k is an arbitrary parameter. This is achieved by, for example, changing specific information such as a date of birth, to a less specific counterpart such as a year of birth.; (cont.) Previous studies have shown that achieving k-anonymity while minimizing information loss is an NP-hard problem; thus a brute force search is out of the question for most real world data sets. In this thesis...
Link permanente para citações:
‣ Clustering and Community Detection in Directed Networks: A Survey
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/08/2013
Português
Relevância na Pesquisa
665.7392%
#Computer Science - Social and Information Networks#Computer Science - Information Retrieval#Physics - Biological Physics#Physics - Computational Physics#Physics - Physics and Society
Networks (or graphs) appear as dominant structures in diverse domains,
including sociology, biology, neuroscience and computer science. In most of the
aforementioned cases graphs are directed - in the sense that there is
directionality on the edges, making the semantics of the edges non symmetric.
An interesting feature that real networks present is the clustering or
community structure property, under which the graph topology is organized into
modules commonly called communities or clusters. The essence here is that nodes
of the same community are highly similar while on the contrary, nodes across
communities present low similarity. Revealing the underlying community
structure of directed complex networks has become a crucial and
interdisciplinary topic with a plethora of applications. Therefore, naturally
there is a recent wealth of research production in the area of mining directed
graphs - with clustering being the primary method and tool for community
detection and evaluation. The goal of this paper is to offer an in-depth review
of the methods presented so far for clustering directed networks along with the
relevant necessary methodological background and also related applications. The
survey commences by offering a concise review of the fundamental concepts and
methodological base on which graph clustering algorithms capitalize on. Then we
present the relevant work along two orthogonal classifications. The first one
is mostly concerned with the methodological principles of the clustering
algorithms...
Link permanente para citações:
‣ Collaboration in computer science: a network science approach. Part I
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
772.9881%
#Computer Science - Social and Information Networks#Computer Science - Digital Libraries#Physics - Physics and Society
Co-authorship in publications within a discipline uncovers interesting
properties of the analysed field. We represent collaboration in academic papers
of computer science in terms of differently grained networks, including those
sub-networks that emerge from conference and journal co-authorship only. We
take advantage of the network science paraphernalia to take a picture of
computer science collaboration including all papers published in the field
since 1936. We investigate typical bibliometric properties like scientific
productivity of authors and collaboration level in papers, as well as
large-scale network properties like reachability and average separation
distance among scholars, distribution of the number of scholar collaborators,
network resilience and dependence on star collaborators, network clustering,
and network assortativity by number of collaborators.
Link permanente para citações:
‣ Automated Query Learning with Wikipedia and Genetic Programming
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/12/2010
Português
Relevância na Pesquisa
668.7219%
#Computer Science - Artificial Intelligence#Computer Science - Information Retrieval#Computer Science - Learning#Computer Science - Neural and Evolutionary Computing#68P20, 68Txx#H.3.1#H.3.3#G.1.6#H.2.4
Most of the existing information retrieval systems are based on bag of words
model and are not equipped with common world knowledge. Work has been done
towards improving the efficiency of such systems by using intelligent
algorithms to generate search queries, however, not much research has been done
in the direction of incorporating human-and-society level knowledge in the
queries. This paper is one of the first attempts where such information is
incorporated into the search queries using Wikipedia semantics. The paper
presents an essential shift from conventional token based queries to concept
based queries, leading to an enhanced efficiency of information retrieval
systems. To efficiently handle the automated query learning problem, we propose
Wikipedia-based Evolutionary Semantics (Wiki-ES) framework where concept based
queries are learnt using a co-evolving evolutionary procedure. Learning concept
based queries using an intelligent evolutionary procedure yields significant
improvement in performance which is shown through an extensive study using
Reuters newswire documents. Comparison of the proposed framework is performed
with other information retrieval systems. Concept based approach has also been
implemented on other information retrieval systems to justify the effectiveness
of a transition from token based queries to concept based queries.; Comment: 44 pages
Link permanente para citações:
‣ Collaboration in computer science: a network science approach. Part II
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/04/2011
Português
Relevância na Pesquisa
770.2131%
#Computer Science - Social and Information Networks#Computer Science - Digital Libraries#Physics - Physics and Society
We represent collaboration of authors in computer science papers in terms of
both affiliation and collaboration networks and observe how these networks
evolved over time since 1960. We investigate the temporal evolution of
bibliometric properties, like size of the discipline, productivity of scholars,
and collaboration level in papers, as well as of large-scale network
properties, like reachability and average separation distance among scientists,
distribution of the number of scholar collaborators, network clustering and
network assortativity by number of collaborators.
Link permanente para citações:
‣ Multislice Modularity Optimization in Community Detection and Image Segmentation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/11/2012
Português
Relevância na Pesquisa
769.4218%
#Computer Science - Social and Information Networks#Computer Science - Computer Vision and Pattern Recognition#Physics - Data Analysis, Statistics and Probability#Physics - Physics and Society
Because networks can be used to represent many complex systems, they have
attracted considerable attention in physics, computer science, sociology, and
many other disciplines. One of the most important areas of network science is
the algorithmic detection of cohesive groups (i.e., "communities") of nodes. In
this paper, we algorithmically detect communities in social networks and image
data by optimizing multislice modularity. A key advantage of modularity
optimization is that it does not require prior knowledge of the number or sizes
of communities, and it is capable of finding network partitions that are
composed of communities of different sizes. By optimizing multislice modularity
and subsequently calculating diagnostics on the resulting network partitions,
it is thereby possible to obtain information about network structure across
multiple system scales. We illustrate this method on data from both social
networks and images, and we find that optimization of multislice modularity
performs well on these two tasks without the need for extensive
problem-specific adaptation. However, improving the computational speed of this
method remains a challenging open problem.; Comment: 3 pages, 2 figures, to appear in IEEE International Conference on
Data Mining PhD forum conference proceedings
Link permanente para citações:
‣ Static and Dynamic Aspects of Scientific Collaboration Networks
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/06/2013
Português
Relevância na Pesquisa
665.8124%
#Computer Science - Social and Information Networks#Computer Science - Digital Libraries#Physics - Physics and Society
Collaboration networks arise when we map the connections between scientists
which are formed through joint publications. These networks thus display the
social structure of academia, and also allow conclusions about the structure of
scientific knowledge. Using the computer science publication database DBLP, we
compile relations between authors and publications as graphs and proceed with
examining and quantifying collaborative relations with graph-based methods. We
review standard properties of the network and rank authors and publications by
centrality. Additionally, we detect communities with modularity-based
clustering and compare the resulting clusters to a ground-truth based on
conferences and thus topical similarity. In a second part, we are the first to
combine DBLP network data with data from the Dagstuhl Seminars: We investigate
whether seminars of this kind, as social and academic events designed to
connect researchers, leave a visible track in the structure of the
collaboration network. Our results suggest that such single events are not
influential enough to change the network structure significantly. However, the
network structure seems to influence a participant's decision to accept or
decline an invitation.; Comment: ASONAM 2012: IEEE/ACM International Conference on Advances in Social
Networks Analysis and Mining
Link permanente para citações:
‣ GeoDBLP: Geo-Tagging DBLP for Mining the Sociology of Computer Science
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 30/04/2013
Português
Relevância na Pesquisa
667.0281%
#Computer Science - Social and Information Networks#Computer Science - Digital Libraries#Physics - Physics and Society
Many collective human activities have been shown to exhibit universal
patterns. However, the possibility of universal patterns across timing events
of researcher migration has barely been explored at global scale. Here, we show
that timing events of migration within different countries exhibit remarkable
similarities. Specifically, we look at the distribution governing the data of
researcher migration inferred from the web. Compiling the data in itself
represents a significant advance in the field of quantitative analysis of
migration patterns. Official and commercial records are often access
restricted, incompatible between countries, and especially not registered
across researchers. Instead, we introduce GeoDBLP where we propagate
geographical seed locations retrieved from the web across the DBLP database of
1,080,958 authors and 1,894,758 papers. But perhaps more important is that we
are able to find statistical patterns and create models that explain the
migration of researchers. For instance, we show that the science job market can
be treated as a Poisson process with individual propensities to migrate
following a log-normal distribution over the researcher's career stage. That
is, although jobs enter the market constantly, researchers are generally not
"memoryless" but have to care greatly about their next move. The propensity to
make k>1 migrations...
Link permanente para citações:
‣ Maps of Computer Science
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 09/04/2013
Português
Relevância na Pesquisa
669.31984%
#Computer Science - Information Retrieval#Computer Science - Digital Libraries#Physics - Physics and Society#H.3.3#G.2.2#I.5.4#I.2.7
We describe a practical approach for visual exploration of research papers.
Specifically, we use the titles of papers from the DBLP database to create what
we call maps of computer science (MoCS). Words and phrases from the paper
titles are the cities in the map, and countries are created based on word and
phrase similarity, calculated using co-occurrence. With the help of heatmaps,
we can visualize the profile of a particular conference or journal over the
base map. Similarly, heatmap profiles can be made of individual researchers or
groups such as a department. The visualization system also makes it possible to
change the data used to generate the base map. For example, a specific journal
or conference can be used to generate the base map and then the heatmap
overlays can be used to show the evolution of research topics in the field over
the years. As before, individual researchers or research groups profiles can be
visualized using heatmap overlays but this time over the journal or conference
base map. Finally, research papers or abstracts easily generate visual
abstracts giving a visual representation of the distribution of topics in the
paper. We outline a modular and extensible system for term extraction using
natural language processing techniques...
Link permanente para citações:
‣ Social Dynamics of Science
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/09/2012
Português
Relevância na Pesquisa
671.1724%
#Physics - Physics and Society#Computer Science - Digital Libraries#Computer Science - Social and Information Networks
The birth and decline of disciplines are critical to science and society.
However, no quantitative model to date allows us to validate competing theories
of whether the emergence of scientific disciplines drives or follows the
formation of social communities of scholars. Here we propose an agent-based
model based on a \emph{social dynamics of science,} in which the evolution of
disciplines is guided mainly by the social interactions among scientists. We
find that such a social theory can account for a number of stylized facts about
the relationships between disciplines, authors, and publications. These results
provide strong quantitative support for the key role of social interactions in
shaping the dynamics of science. A "science of science" must gauge the role of
exogenous events, such as scientific discoveries and technological advances,
against this purely social baseline.
Link permanente para citações:
‣ Measuring the Meaning of Words in Contexts: An automated analysis of controversies about Monarch butterflies, Frankenfoods, and stem cells
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 17/11/2009
Português
Relevância na Pesquisa
771.2897%
#Computer Science - Computation and Language#Computer Science - Information Retrieval#Physics - Physics and Society
Co-words have been considered as carriers of meaning across different domains
in studies of science, technology, and society. Words and co-words, however,
obtain meaning in sentences, and sentences obtain meaning in their contexts of
use. At the science/society interface, words can be expected to have different
meanings: the codes of communication that provide meaning to words differ on
the varying sides of the interface. Furthermore, meanings and interfaces may
change over time. Given this structuring of meaning across interfaces and over
time, we distinguish between metaphors and diaphors as reflexive mechanisms
that facilitate the translation between contexts. Our empirical focus is on
three recent scientific controversies: Monarch butterflies, Frankenfoods, and
stem-cell therapies. This study explores new avenues that relate the study of
co-word analysis in context with the sociological quest for the analysis and
processing of meaning.
Link permanente para citações:
‣ The Import and Export of Cognitive Science
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/11/2009
Português
Relevância na Pesquisa
666.0726%
From its inception, a large part of the motivation for Cognitive Science has
been the need for an interdisciplinary journal for the study of minds and
intelligent systems. One threat to the interdisciplinarity of Cognitive
Science, both the field and journal, is that it may become, or already be, too
dominated by psychologists. In 2005, psychology was a keyword for 51% of
submissions, followed distantly by linguistics (17%), artificial intelligence
(13%), neuroscience (10%), computer science (9%), and philosophy (8%). The
Institute for Scientific Information (ISI) gathers data not only on how
individual articles cite one another, but also on macroscopic citation patterns
among journals. Journals or sets of journals can be considered as proxies for
fields. As fields become established, they often create journals. By studying
the patterns of citations among journals that cite and are cited by Cognitive
Science, we can better: 1) appreciate the scholarly ecology surrounding the
journal and the journals role within this ecology, 2) establish competitor and
alternate journals, and 3) determine the natural clustering of fields related
to cognitive science.
Link permanente para citações:
‣ Seats at the table: the network of the editorial boards in information and library science
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/02/2011
Português
Relevância na Pesquisa
665.8134%
#Computer Science - Digital Libraries#Computer Science - Social and Information Networks#Physics - Physics and Society
The structural properties of the network generated by the editorial
activities of the members of the boards of "Information Science & Library
Science" journals are explored through network analysis techniques. The crossed
presence of scholars on editorial boards, the phenomenon called interlocking
editorship, is considered a proxy of the similarity of editorial policies. The
evidences support the idea that this group of journals is better described as a
set of only relatively connected subfields. In particular two main subfield are
identified, consisting of research oriented journals devoted respectively to
LIS and MIS. The links between these two subsets are weak. Around these two
subsets there are a lot of (relatively) isolated professional journals or
journals characterized more by their subject-matter content than by their focus
on information flows. It is possible to suggest that this configuration of the
network may be the consequence of the youthfulness of Information Science &
Library Science, which has not permitted yet to reach a general consensus
through scholars on research aims, methods and instruments.; Comment: 12 pages, 3 figures, 3 tables Accepted for publication. Journal of
Informetrics
Link permanente para citações: