Object Files Research Articles

CompCertELF: verified separate compilation of C programs into ELF object files

We present CompCertELF, the first extension to CompCert that supports verified compilation from C programs all the way to a standard binary file format, i.e., the ELF object format. Previous work on Stack-Aware CompCert provides a verified compilation chain from C programs to assembly programs with a realistic machine memory model. We build CompCertELF by modifying and extending this compilation chain with a verified assembler which further transforms assembly programs into ELF object files. CompCert supports large-scale verification via verified separate compilation: C modules can be written and compiled separately, and then linked together to get a target program that refines the semantics of the program linked from the source modules. However, verified separate compilation in CompCert only works for compilation to assembly programs, not to object files. For the latter, the main difficulty is to bridge the two different views of linking: one for CompCert's programs that allows arbitrary shuffling of global definitions by linking and the other for object files that treats blocks of encoded definitions as indivisible units. We propose a lightweight approach that solves the above problem without any modification to CompCert's framework for verified separate compilation: by introducing a notion of syntactical equivalence between programs and proving the commutativity between syntactical equivalence and the two different kinds of linking, we are able to transit from the more abstract linking operation in CompCert to the more concrete one for ELF object files. By applying this approach to CompCertELF, we obtain the first compiler that supports verified separate compilation of C programs into ELF object files.

A simulation framework for bio-inspired sonar sensing with Unmanned Aerial Vehicles.

We introduce a unified simulation framework that generates natural sensing environments and produces biosonar echoes under various sensing scenarios. This framework produces rich sensory data with environmental information completely known, thus can be used for the training of robotic algorithms for biosonar-based Unmanned Aerial Vehicles. The simulated environment consists of random trees with full geometry of the tree foliage. To simulate a single tree, we adopt the Lindenmayer system to generate the initial branching pattern and integrate that with the available measurements of the 3D computer-aided design object files to create natural-looking branches, sub-branches, and leaves. A forest is formed by simulating trees at random locations generated by using an inhomogeneous Poisson process. While our simulated environments can be generally used for testing other sensors and training robotic algorithms, in this study we focus on testing bat-inspired Unmanned Aerial Vehicles that recreate bat’s flying behavior through biosonar sensors. To this end, we also introduce an foliage echo simulator that produces biosonar echoes while mimicking bat’s biosonar system. We demonstrate the application of the proposed simulation framework by generating real-world scenarios with multiple trees and computing the resulting impulse responses under static or dynamic motions of an Unmanned Aerial Vehicle.

Why Not Just Features? Reconsidering Infants' Behavior in Individuation Tasks.

It counts as empirically proven that infants can individuate objects. Object individuation is assumed to be fundamental in the development of infants’ ontology within the object-first account. It crucially relies on an object-file (OF) system, representing both spatiotemporal (“where”) and categorical (“what”) information about objects as solid, cohesive bodies moving continuously in space and time. However, infants’ performance in tasks requiring them to use featural information to detect individuation violations appears to be at odds with the object-first account. In such cases, infants do not appear to be able to develop correct expectations about the numerosity of objects. Recently, proponents of the object-first account proposed that these individuation failures result from integration errors between the OF system and an additional physical reasoning system. We are going to argue that the predictions of a feature-based physical-reasoning (PR) system are sufficient for explaining infants’ behavior. The striking predictive power of the PR system calls into question the relevance of the OF system and, thereby, challenges the assumption that infants can individuate objects early on.

The role of object files in visual working memory: Facilitating integration over longer timescales for moving objects

The role of object files in visual working memory: Facilitating integration over longer timescales for moving objects

Automatic Grading for Complex Multifile Programs

This paper presents an automatic grading method DGRADER, which handles complex multifile programs. Both the dynamic and the static grading support multifile program analysis. So, it can be an advantage to handle complex programming problem which requires more than one program file. Dynamic analysis takes advantage of object file linker in compilation to link complex multifile program. The static grading module consists of the following steps. Firstly, the program is parsed into abstract syntax tree, which is mapped into abstract syntax tree data map. Then, the information of preprocessor is used for linking external sources called in main program by complex multifile program linker-fusion algorithm. Next, standardization process is performed for problematic code removal, unused function removal, and function sequence ordering based on function call. Finally, program matching successfully tackles structure variance problem by previous standardization process and by simple tree matching using tag classifier. The novelty of the approach is that it handles complex multifile program analysis with flexible grading with consideration of modularity and big scale of programming problem complexity. The results have shown improvement in grading precision which gives reliable grading score delivered with intuitive system.

Using temporal EEG signal decomposition to identify specific neurophysiological correlates of distractor-response bindings proposed by the theory of event coding

The ability to cope with distracting information is a major requirement for goal-directed behavior. It is particularly challenged when distracting information is either potentially relevant or temporally close to goal-directed responses, resulting in so-called distractor-response bindings. According to the theory of event coding (TEC), distractor-response bindings should be reflected by processes in the event file, but not in object file (which stores stimulus features) or the action file (which stores response features). But even though the predictions of this theory are quite elaborated, their electrophysiological underpinnings and the associated functional neuroanatomical structures have remained largely elusive. To examine this, we used a distractor-response binding paradigm in combination with temporal EEG signal decomposition (RIDE) and source localization techniques. We showed that distractor-response binding effects are exclusively evident in the N450 time window of the central C-cluster. Source reconstructions revealed that distractor-response binding effects were associated with brain regions involved in updating internal representations by using task-relevant information to decide on response execution (temporo-parietal junction, BA40), alongside with brain regions involved in conflict resolution processes (right middle frontal gyrus, BA8). Our results suggest that RIDE can be used to dissociate binding processes from stimulus- and response-related processes. On top of this, the results of EEG decomposition match the key assumption of the TEC, that distractor-response bindings occur in event files, but not in object files or action files. The results show how cognitive-theoretical frameworks, such as the TEC, can directly be mapped onto the underlying neurophysiological processes using EEG signal decomposition.

Validation Analysis of Scalable Vector Graphics (SVG) File Upload using Magic Number and Document Object Model (DOM)

The use of technology is increasing rapidly, such as applications or services connected to the Internet. Security is considered necessary because of the growing and increasing use of digital systems. With the number of threats to attacks on digital form or server systems is required to handle the risk of attacks on the server, the file upload feature. The system usually processes the file upload feature on a website or server with server-side (back-end) validation or filtering of digital object file types or a client-side (front-end) web browser in HTML or Javascript. Filtering techniques for Scalable Vector Graphics (SVG) usually files only see the file extension or Multipurpose Internet Mail Extension (MIME) type of an uploaded file. However, this filtering can still manipulate, for example, in ASCII prefix checking, which has two writes, namely "<?xml” and “<svg ”. SVG files do not contain metadata such as image encoded in JPEG or PNG files. This problem can overcome by adding filtering techniques to check the validation of a file with validation of eXtensible Markup Language (XML) using magic numbers and the Document Object Model (DOM). This research developed using the waterfall method and black-box security testing refers to a software security testing method in which security controls, defense, and application design are tested. Handling of security validation for uploading SVG files using file extensions and MIME types has a success rate of 75 percent from the eight tested scenarios while handling using file extensions, magic numbers, and Document Object Model (DOM) produces a success rate of 100 percent from 8 test scenarios. Testing uses a black-box so that handling using the file extension, magic number, and Document Object Model (DOM) is better than using only file extensions and mime types.

Implementation of Parallelized K-means and K-Medoids++ Clustering Algorithms on Hadoop Map Reduce Framework

The electronic information from online newspapers, journals, conference proceedings website pages and emails are growing rapidly which are generating huge amount of data. Data grouping has been gotten impressive consideration in numerous applications. The size of data is raised exponentially due to the advancement of innovation and development, makes clustering of vast size of information, a challenging issue. With the end goal to manage the issue, numerous scientists endeavor to outline productive parallel clustering representations to be needed in algorithms of hadoop. In this paper, we show the implementation of parallelized K-Means and parallelized K-Medoids algorithms for clustering an large data objects file based on MapReduce for grouping huge information. The proposed algorithms combines initialization algorithm with Map Reduce framework to reduce the number of iterations and it can scale well with the commodity hardware as the efficient process for large dataset processing. The outcome of this paper shows the implementation of each algorithms.

Object file system software experiments about the notion of number in humans and machines

Object file system software experiments about the notion of number in humans and machines

IMPLEMENTASI METODE MD5 UNTUK MENDETEKSI ORISINALITAS FILE AUDIO

The problem of the originality of the file is about how the file can be maintained its authenticity and ensures that the file has never been changed at all. In this study the object file used is the audio file. The process of manipulating files often occurs during data transmission activities from the sender to the recipient. The solution that can be done to handle the crime of manipulation is to apply a hash type cryptographic technique in which the hash value is encrypted from an audio file that can be used as a keyword to ensure the audio file has never been manipulated or has been manipulated. The hash cryptographic algorithm used is the type of MD5 algorithm. The results obtained from the process of implementing the MD5 algorithm using MATLAB R2010a software and the HASH Pro application are audio file hash codes. Keywords: Implementation, Encryption, Decryption, MD5 Method, Cryptography.

Object files and unconscious perception: a reply to Quilty-Dunn

Abstract A wealth of cases – most notably blindsight and priming under inattention or suppression – have convinced philosophers and scientists alike that perception occurs outside awareness. In recent work (Phillips 2016a, 2018; Phillips and Block 2017, Peters et al. 2017), I dispute this consensus, arguing that any putative case of unconscious perception faces a dilemma. The dilemma divides over how absence of awareness is established. If subjective reports are used, we face the problem of the criterion: the concern that such reports underestimate conscious experience (Eriksen 1960, Holender 1986, Peters and Lau 2015). If objective measures are used, we face the problem of attribution: the concern that the case does not involve genuine individual-level perception. Quilty-Dunn (2019) presents an apparently compelling example of unconscious perception due to Mitroff et al. (2005) which, he contends, evades this dilemma. The case is fascinating. However, as I here argue, it does not escape the dilemma’s clutches.

Object correspondence: Using perceived causality to infer how the visual system knows what went where

Anne Treisman and colleagues developed an influential theoretical framework surrounding the construct of "object files" as a means of understanding the functional need for an episodic representation of objects as they move, change, disappear, and reappear from view (Kahneman, Treisman, & Gibbs, Cognitive Psychology, 24, 175-219, 1992; Treisman, The Quarterly Journal of Experimental Psychology, 40, 201-237, 1988). Within that framework, object files are defined through the process of object correspondence, whereby stimuli are associated with and represented as later instantiations of existing object representations and are used to selectively update those representations. A central assertion of the object file framework is that object correspondence is established on the basis of spatiotemporal continuity, without regard to feature information. We tested this assertion by investigating whether feature information, separate from spatiotemporal information, can determine how object correspondence is resolved. We used the perception of causality in simple dynamic displays, which provides a means of inferring how object correspondence is resolved. We found that, contrary to the spatiotemporal dominance assertion, feature information is used to resolve object correspondence. We suggest that the object-file framework be extended to reflect the importance of both feature and spatiotemporal information in establishing and maintaining episodic object representations.

What was that object? On the role of identity information in the formation of object files and conscious object perception.

Object files are a psychological representation that allows the human brain to keep track of objects, as they move and change across time. The question regarding what information is used to individuate versus update object files has been the focus of considerable scientific debate. Historically, the role of an object's spatiotemporal history was emphasised, whereas more recent work has demonstrated a key contribution from surface features, such as colour. The purpose of the present study was to investigate the role of identity-level information in the formation and individuation of object files, and how it compares to the contribution of featural information. Using a modified spatial repetition-blindness paradigm, across four experiments, there was convergent evidence that surface features contribute to the formation of object files, whereas the role of identity information was at best much smaller and less reliable than the clear contribution from surface features, and the most parsimonious explanation is that it was not present at all.

Robust color-shape binding representations for multiple objects in visual working memory.

The nature of feature-bound object representations in visual working memory (VWM) remains unclear. Many studies claim that they are held by a resource-limited system and are fragile. Using a novel paradigm called the redundant feature reviewing task, the current study showed that color-shape binding representations for multiple objects are maintained and matched with perceptual representation in a robust fashion in VWM. A set of features was presented in a two-object memory display, followed by a linking display in which placeholders either moved or stayed. Then participants judged if a single object probe contained any features of the memory display, regardless of object correspondence. The advantage of color-shape conjunction relative to single features, as indexed by feature coactivation, was retained in the memory matching within the same object and between different objects, regardless of object motion. In contrast, the object-specific preview benefit (OSPB), an index of accessibility to memory representations, was reduced when objects moved, suggesting that motion disrupts the spatiotemporal continuity of memory representations. A meta-analysis of the magnitude of the OSPB in the moving condition across the experiments showed a significant OSPB, suggesting that object file representations bound to spatiotemporal locations are responsible for feature coactivation. Taken together, these findings suggest that the nonspatial features of multiple objects are bound and maintained in VWM, in a robust fashion, regardless of the objects' motion. The cost of object motion in the memory matching performance likely reflects the correspondence between identity and spatiotemporal location, rather than the binding of nonspatial features. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

FESTR: Finite-Element Spectral Transfer of Radiation spectroscopic modeling and analysis code (New Version Announcement)

We report on the release of a new version of the FESTR (P. Hakel, Comput. Phys. Commun. 207 (2016) 415–425., https://github.com/LANLhakel/FESTR) spectral postprocessor of hydrodynamic simulations of hot, dense plasmas. Based on given time histories of one-, two-, and three-dimensional spatial distributions of materials, and their local temperature and density conditions, spectroscopically-resolved signals are computed. The effects of radiation emission and absorption by the plasma on the emergent spectra are simultaneously taken into account. This program can also be used independently of hydrodynamic calculations to analyze available experimental data with the goal of inferring plasma conditions. NEW VERSION PROGRAM SUMMARYProgram Title: FESTRProgram Files doi:http://dx.doi.org/10.17632/npvtbd7kfg.2Licensing provisions: BSD 3-clause licenseProgramming language: C++Journal reference of previous version: P. Hakel, Comput. Phys. Commun. 207 (2016) 415–425.Does the new version supersede the previous version?: YesReasons for the new version: Parallelization, bug fixes, new features and copyrightSummary of revisions: The copyright notice was changed to reflect the transition of the Los Alamos National Laboratory M&O contract from Los Alamos National Security, LLC, to Triad National Security, LLC. The code was parallelized across time steps using MPI and selected loops were parallelized with OpenMP threading; the makefile now takes additional command-line arguments to invoke these capabilities. The makefile was generalized to use wildcard functionality and placed into the new directory named “common” along with MPI and unit-test relevant source files. Object files are now assembled into library (“*.a”) archive files before linking with the object file containing the “main” function (this change should facilitate the reuse of FESTR functions in other possible future projects.) New “tracking” members were added to classes Detector and Ray to mark whether partial spectral results (along the specified Rays) should also be output (the default is “no” i.e., “false”); relevant unit tests were added or modified accordingly. Several bugs were found and corrected. Additional details and the full history of the development of this program can be found in the “README.md” and “about.txt” files located in the top directory of this package.Nature of problem: Calculation of spectral signals by postprocessing hydrodynamics simulations. Analysis of experimental spectroscopic data to infer plasma temperature and density conditions, and its chemical composition. Simultaneous treatment of spatial non-uniformity (on 3D unstructured meshes) along with spectroscopic-quality radiation transport.Solution method: Rays are cast across a 3D unstructured mesh that characterizes local temperature, density, and chemical composition of the material. Analytic solution to the 1D (along the ray) steady-state, local radiation transport equation is repeatedly used to gradually build a synthetic spectrum for each ray.Restrictions: Steady-state approximation of the radiation transport equation is used. Scattering as a radiation source is not included. Given plasma conditions are considered fixed; potential feedback of computed radiation back into plasma temperature and equation-of-state is neglected. Doppler shifts are not modeled at this time. The quality of the computed results critically depends on the accuracy of external atomic databases used as input by FESTR. Polygon objects are assumed to be convex at present.

Universal framework for remote firmware updates of low-power devices

Remote firmware updates are nowadays an important part of any firmware for embedded devices. In systems with dozens or even hundreds of devices, for example wireless sensor networks, cyber–physical systems, smart systems, etc., reprogramming each device manually just to fix a simple issue would be ineffective. We present a novel multiplatform framework for remote updates of low-power embedded devices. Our approach achieves its multiplatform nature through the availability of standard object files for almost every existing platform. We avoid any alteration of the source code and focus on thorough analysis of the firmware outline and generation of the linker commands. The framework tracks changes in the firmware, improves similarity between various versions and generates a differential file, called delta or patch. Reducing data shared between devices with delta files and minimizing the amount of memory operations improves the energy efficiency of an update. The process reduces the update size by approximately 80% compared to the full firmware transfer and improves over existing differencing solutions variously from 5% to 50%. The framework is designed for battery powered, physically inaccessible low-power devices in heterogeneous systems but can be used for any device connected to any network.

Collecting Virtual and Augmented Reality in the Twenty-First Century Library

In this paper, we discuss possible pedagogical applications for virtual and augmented reality (VR and AR), within a humanities/social sciences curriculum, articulating a critical need for academic libraries to collect and curate 3D objects. We contend that building infrastructure is critical to keep pace with innovative pedagogies and scholarship. We offer theoretical avenues for libraries to build a repository 3D object files to be used in VR and AR tools and sketch some anticipated challenges. To build an infrastructure to support VR/AR collections, we have collaborated with College of Liberal Arts to pilot a program in which Libraries and CLA faculty work together to bring VR/AR into liberal arts curricula.

Lightweight data management with dtool.

The explosion in volumes and types of data has led to substantial challenges in data management. These challenges are often faced by front-line researchers who are already dealing with rapidly changing technologies and have limited time to devote to data management. There are good high-level guidelines for managing and processing scientific data. However, there is a lack of simple, practical tools to implement these guidelines. This is particularly problematic in a highly distributed research environment where needs differ substantially from group to group and centralised solutions are difficult to implement and storage technologies change rapidly. To meet these challenges we have developed dtool, a command line tool for managing data. The tool packages data and metadata into a unified whole, which we call a dataset. The dataset provides consistency checking and the ability to access metadata for both the whole dataset and individual files. The tool can store these datasets on several different storage systems, including a traditional file system, object store (S3 and Azure) and iRODS. It includes an application programming interface that can be used to incorporate it into existing pipelines and workflows. The tool has provided substantial process, cost, and peace-of-mind benefits to our data management practices and we want to share these benefits. The tool is open source and available freely online at http://dtool.readthedocs.io.

The Pocket-book and the Pigeon-hole: &lt;em&gt;Lady Audley's Secret&lt;/em&gt; and the Files of Victorian Fiction

This article argues that the Victorian novel is governed by the logic of storage: the accumulation of data and the deferral of action. Focusing on Mary Elizabeth Braddon's Lady Audley's Secret (1862), I demonstrate that the sensation novel is caught between the winnowing directive of the detection plot and the capaciousness of Victorian literary form. The novel's many objects register information and delay narrative, but they never quite get activated as clues. I track three kinds of paper objects—files, memoranda, and keepsakes—all of which linger in storage, declining in value and awaiting an opportunity for transmission that might never arrive. Disposable yet persistent, paper evokes the cultural confusion over how to save and what, if anything, to discard. I contextualize the novel with government records and journalism from the period, all of which express similar archival anxieties. Braddon's novel ultimately muddles the distinction between clue and litter, keepsake and junk, archive and hoard, as well as between significant and insignificant narrative information.

Exploiting Binary-Level Code Virtualization to Protect Android Applications Against App Repackaging

Application repackaging is a severe problem for Android systems. Many Android malware programs pass the mobile platform fundamental security barriers through repackaging other legitimate apps. Most of the existing anti-repackaging schemes only work at the Android DEX bytecode level, but not for the shared object files consisting of native ARM-based machine instructions. Lacking the protection at the native machine code level opens a door for attackers to launch repackaging attacks on the shared libraries that are commonly used on Android apps. This paper presents CodeCloak, a novel anti-repackaging system to protect Android apps at the native code level. CodeCloak employs binary-level code virtualization techniques to protect the target application. At the native machine code level, it uses a newly designed stack-based virtualization structure to obfuscate and protect critical algorithm implementations that have been compiled into native instructions. It leverages multiple dynamic code protection schemes to increase the diversity of the program behavior at runtime, aiming to increase the difficulties for performing code reverse engineering. We evaluate CodeCloak under typical app repackaging scenarios. Experimental results show that CodeCloak can effectively protect apps against repackaging attacks at the cost of minimum overhead.