1,720,971 research outputs found
Session types in practical programming
Get PDFPrograms are more distributed and concurrent today than ever before, and structural communications are at the core. Constructing and debugging such programs are hard due to the lack of formal specifications and verifications of concurrency. Recent advances in type systems allow us to specify the structures of communications as session types, thus enabling static type checking of the usages of communication channels against protocols. The soundness of session type systems implies communication fidelity and absence of deadlock. This work proposes to formalize multiparty dependent session types as an expressive and practical type discipline for enforcing communication protocols. The type system is formulated in the setting of multi-threaded λ-calculus with inspirations from multirole logic. It is sound, and it provides linearity and coherence guarantees entirely statically. The type system supports recursion and polymorphism. The formulation is particularly suitable for practical implementation, and this work provides such a runtime implementation
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A dependently typed programming language with dynamic equality
Get PDFDependent types offer a uniform foundation for both proof systems and programming languages.
While the proof systems built with dependent types have become relatively popular, dependently typed programming languages are far from mainstream.
One key issue with existing dependently typed languages is the overly conservative definitional equality that programmers are forced to use.
When combined with a traditional typing workflow, these systems can be quite challenging and require a large amount of expertise to master.
This thesis explores an alternative workflow and a more liberal handling of equality.
Programmers are given warnings that contain the same information as the type errors that would be given by an existing system.
Programmers can run these programs optimistically, and they will behave appropriately unless a direct contradiction confirming the warning is found.
This is achieved by localizing equality constraints using a new form of elaboration based on bidirectional type inference.
These local checks, or casts, are given a runtime behavior (similar to those of contracts and monitors).
The elaborated terms have a weakened form of type soundness: they will not get stuck without an explicit counter example.
The language explored in this thesis will be a Calculus of Constructions like language with recursion, type-in-type, data types with dependent indexing and pattern matching.
Several meta-theoretic results will be presented.
The key result is that the core language, called the cast system, "will not get stuck without a counter example"; a result called cast soundness.
A proof of cast soundness is fully worked out for the fragment of the system without user defined data, and a Coq proof is available. Several other properties based on the gradual guarantees of gradual typing are also presented.
In the presence of user defined data and pattern matching these properties are conjectured to hold.
A prototype implementation of this work is available
Program synthesis and vulnerability injection using a Grammar VAE
Get PDFThe ability to automatically detect and repair vulnerabilities in code before deployment has become the subject of increasing attention. Some approaches to this problem rely on machine learning techniques, however the lack of datasets–code samples labeled as containing a vulnerability or not–presents a barrier to performance. We design and implement a deep neural network based on the recently developed Grammar Variational Autoencoder (VAE) architecture to generate an arbitrary number of unique C functions labeled in the aforementioned manner. We make several improvements on the original Grammar VAE: we guarantee that every vector in the neural network’s latent space decodes to a syntactically valid C function; we extend the Grammar VAE into a context-sensitive environment; and we implement a semantic repair algorithm that transforms syntactically valid C functions into fully semantically valid C functions that compile and execute. Users can control the semantic qualities of output functions with our constraint system. Our constraints allow users to modify the return type, change control flow structures, inject vulnerabilities into generated code, and more. We demonstrate the advantages of our model over other program synthesis models targeting similar applications. We also explore alternative applications for our model, including code plagiarism detection and compiler fuzzing, testing, and optimization
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
- …
