Programming Languages and Compilers Commons^™

Technologies For Ubiquitous Supercomputing: A Java Interface To The Nexus Communication System, Ian Foster, George K. Thiruvathukal, Steven Tuecke

George K. Thiruvathukal

We use the term ubiquitous supercomputing to refer to systems that integrate low- and mid-range computing systems, advanced networks and remote high-end computers with the goal of enhancing the computational power accessible from local environments. Such systems promise to enable new applications in areas as diverse as smart instruments and collaborative environments. However, they also demand tools for transporting code between computers and for establishing flexible, dynamic communication structures. In this article, we propose that these requirements be satisfied by introducing Java classes that implement the global pointer and remote service request mechanisms defined by a communication library called Nexus. …

Model Checking In The Absence Of Code, Model And Properties, David Lo, Siau-Cheng Khoo

David LO

Model checking is a major approach in ensuring software correctness. It verifies a model converted from code against some formal properties. However, difficulties and programmers ’ reluctance to formalize formal properties have been some hurdles to its widespread industrial adoption. Also, with the advent of commercial off-the-shelf (COTS) components provided by third party vendors, model checking is further challenged as often only a binary version of the code is provided by vendors. Interestingly, latest instrumentation tools like PIN and Valgrind have enable execution traces to be collected dynamically from a running program. In this preliminary study, we investigate what can …

Mining Scenario-Based Specifications With Value-Based Invariants, David Lo, Shahar Maoz

David LO

There have been a number of studies on mining candidate specifications from execution traces. Some extract specifications corresponding to value-based invariants, while others work on inferring ordering constraints. In this work, we merge our previous work on mining scenario-based specifications, extracting ordering constraints in the form of live sequence charts (LSC), a visual specification language, with Daikon, a tool for mining value-based invariants. The resulting approach strengthens the expressive power of the mined scenarios by enriching them with scenario-specific value-based invariants. The concept is illustrated using a preliminary case study on a real application.

An Efficient Algorithm For Learning Event-Recording Automata, Shang-Wei Lin, Étienne André, Jin Song Dong, Jun Sun, Yang Liu

Research Collection School Of Computing and Information Systems

In inference of untimed regular languages, given an unknown language to be inferred, an automaton is constructed to accept the unknown language from answers to a set of membership queries each of which asks whether a string is contained in the unknown language. One of the most well-known regular inference algorithms is the L* algorithm, proposed by Angluin in 1987, which can learn a minimal deterministic finite automaton (DFA) to accept the unknown language. In this work, we propose an efficient polynomial time learning algorithm, TL*, for timed regular language accepted by event-recording automata. Given an unknown timed regular language, …

Prts: An Approach For Model Checking Probabilistic Real-Time Hierarchical Systems, Jun Sun, Yang Liu, Songzheng Song, Jin Song Dong, Xiaohong Li

Research Collection School Of Computing and Information Systems

Model Checking real-life systems is always difficult since such systems usually have quantitative timing factors and work in unreliable environment. The combination of real-time and probability in hierarchical systems presents a unique challenge to system modeling and analysis. In this work, we develop an automated approach for verifying probabilistic, real-time, hierarchical systems. Firstly, a modeling language called PRTS is defined, which combines data structures, real-time and probability. Next, a zone-based method is used to build a finite-state abstraction of PRTS models so that probabilistic model checking could be used to calculate the probability of a system satisfying certain property. We …

Cooperative Reinforcement Learning In Topology-Based Multi-Agent Systems, Dan Xiao, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Topology-based multi-agent systems (TMAS), wherein agents interact with one another according to their spatial relationship in a network, are well suited for problems with topological constraints. In a TMAS system, however, each agent may have a different state space, which can be rather large. Consequently, traditional approaches to multi-agent cooperative learning may not be able to scale up with the complexity of the network topology. In this paper, we propose a cooperative learning strategy, under which autonomous agents are assembled in a binary tree formation (BTF). By constraining the interaction between agents, we effectively unify the state space of individual …

Verification Of Orchestration Systems Using Compositional Partial Order Reduction, Tian Huat Tan, Yang Liu, Jun Sun, Jin Song Dong

Research Collection School Of Computing and Information Systems

Orc is a computation orchestration language which is designed to specify computational services, such as distributed communication and data manipulation, in a concise and elegant way. Four concurrency primitives allow programmers to orchestrate site calls to achieve a goal, while managing timeouts, priorities, and failures. To guarantee the correctness of Orc model, effective verification support is desirable. Orc has a highly concurrent semantics which introduces the problem of state-explosion to search-based verification methods like model checking. In this paper, we present a new method, called Compositional Partial Order Reduction (CPOR), which aims to provide greater state-space reduction than classic partial …

Towards A Model Checker For Nesc And Wireless Sensor Networks, Manchun Zheng, Jun Sun, Yang Liu, Jin Song Dong, Yu Gu

Research Collection School Of Computing and Information Systems

Wireless sensor networks (WSNs) are expected to run unattendedly for critical tasks. To guarantee the correctness of WSNs is important, but highly nontrivial due to the distributed nature. In this work, we present an automatic approach to directly verify WSNs built with TinyOS applications implemented in the NesC language. To achieve this target, we firstly define a set of formal operational semantics for most of the NesC language structures for the first time. This allows us to capture the behaviors of sensors by labelled transition systems (LTSs), which are the underlying semantic models of NesC programs. Secondly, WSNs are modeled …

Amibe: An Imperative Programming Language With First Class Continuations, Yuting Wang

Master's Theses

A continuation represents the future of an execution. It is often used as an intermediate representation(IR) to compile functional programming languages, make control flow explicit and full beta-reduction(function inlining) possible. Continuations are also a language feature that gives user the ability to completely control the execution control flow(first class continuation). Efficient implementation of first class continuation is important for languages that need non-determinism and backtracking(e.g., COMET). We present a prototype imperative programming language with first class continuation -- AMIBE. AMIBE uses the LLVM compiler infrastructure which is attractive for its optimizing tools and overall modern organization. However, LLVM does not …

Roaming Region For Delaunay Triangulation, Romas James Hada

UNLV Theses, Dissertations, Professional Papers, and Capstones

Delaunay graphs have been used in CAD/CAM, sensor network and geographic information systems. We investigate the reliability properties of nodes in Delaunay graphs. For measuring the reliability we formulate the concept of roaming-region for nodes. A node v with large roaming-region r(v) such that v is positioned near the center of r(v) is identified as a reliable node. We develop algorithms for constructing roaming-regions and present an implementation of the proposed algorithm in the Java programming language.

Formalizing Reusable Aspect-Oriented Concurrency Control, Neelam Soundarajan, Derek Bronish, Raffi T. Khatchadourian

Publications and Research

Java and its library provide powerful concurrency control mechanisms. However, their use can lead to similar synchronization code scattered across multiple classes, synchronization and functional code being tangled together, and similar code being duplicated in many applications. Aspect-oriented (AO) programming makes it possible to address these problems. However, the specific behavior of systems built using AO techniques can be challenging to comprehend. We propose a specification approach to precisely express such systems' critical concurrency and synchronization properties. We illustrate the method with a simple example.

Automatic Content Generation For Video Self Modeling, Ju Shen, Anusha Raghunathan, Sen-Ching S. Cheung, Ravi R. Patel

Computer Science Faculty Publications

Video self modeling (VSM) is a behavioral intervention technique in which a learner models a target behavior by watching a video of him or herself. Its effectiveness in rehabilitation and education has been repeatedly demonstrated but technical challenges remain in creating video contents that depict previously unseen behaviors. In this paper, we propose a novel system that re-renders new talking-head sequences suitable to be used for VSM treatment of patients with voice disorder. After the raw footage is captured, a new speech track is either synthesized using text-to-speech or selected based on voice similarity from a database of clean speeches. …

Combinational Circuit Obfuscation Through Power Signature Manipulation, Hyunchul Ko

Theses and Dissertations

Today's military systems are composed of hardware and software systems, many of which are critical technologies, and must be protected to ensure our adversaries cannot gain any information from a various analysis attacks. Side Channel Analysis (SCA) attacks allow an attacker to gain the significant information from the measured signatures leaked by side-channels such as power consumption, and electro-magnetic emission. In this research the focus on detecting, characterizing, and manipulating the power signature by designing a power signature estimation and manipulation method. This research has determined that the proposed method capable of characterizing and altering the type of power signature …

Intelligent Systems Development In A Non Engineering Curriculum, Emily A. Brand, William L. Honig, Matthew Wojtowicz

Computer Science: Faculty Publications and Other Works

Much of computer system development today is programming in the large - systems of millions of lines of code distributed across servers and the web. At the same time, microcontrollers have also become pervasive in everyday products, economical to manufacture, and represent a different level of learning about system development. Real world systems at this level require integrated development of custom hardware and software.

How can academic institutions give students a view of this other extreme - programming on small microcontrollers with specialized hardware? Full scale system development including custom hardware and software is expensive, beyond the range of any …

On Combining State Space Reductions With Global Fairness Assumptions, Shao Jie Zhang, Jun Sun, Jun Pang, Yang Liu, Jin Song Dong

Research Collection School Of Computing and Information Systems

Model checking has established itself as an effective system analysis method, as it is capable of proving/dis-proving properties automatically. Its application to practical systems is however limited by state space explosion. Among effective state reduction techniques are symmetry reduction and partial order reduction. Global fairness often plays a vital role in designing self-stabilizing population protocols. It is known that combining fairness and symmetry reduction is nontrivial. In this work, we first show that global fairness, unlike weak/strong fairness, can be combined with symmetry reduction. We extend the PAT model checker with the technique and demonstrate its usability by verifying recently …

Efficient Schema Extraction From A Collection Of Xml Documents, Vijayeandra Parthepan

Masters Theses & Specialist Projects

The eXtensible Markup Language (XML) has become the standard format for data exchange on the Internet, providing interoperability between different business applications. Such wide use results in large volumes of heterogeneous XML data, i.e., XML documents conforming to different schemas. Although schemas are important in many business applications, they are often missing in XML documents. In this thesis, we present a suite of algorithms that are effective in extracting schema information from a large collection of XML documents. We propose using the cost of NFA simulation to compute the Minimum Length Description to rank the inferred schema. We also studied …

Parallelizing Scale Invariant Feature Transform On A Distributed Memory Cluster, Stanislav Bobovych

Computer Science and Computer Engineering Undergraduate Honors Theses

Scale Invariant Feature Transform (SIFT) is a computer vision algorithm that is widely-used to extract features from images. We explored accelerating an existing implementation of this algorithm with message passing in order to analyze large data sets. We successfully tested two approaches to data decomposition in order to parallelize SIFT on a distributed memory cluster.

Model-Controller Interfacing Using Struts-Based Web Application, Deepti Bhardwaj

Master's Projects

StrutsHib IDE is an IDE for interfacing the model and controller of a MVC architecture based applications. It is developed using Java-based technologies such as the Struts framework, Hibernate and jQuery. The StrutsHib IDE is a web application. This project implements the part of StrutsHib IDE that makes it easy to create model and controller components. Moreover, it automates the process of database creation for web applications which means the user does not have to be a database expert when dealing with databases. Finally, StrutsHib IDE takes all the advantages of a web-based application and provides lot of flexibility to …

Decompiler For Pseudo Code Generation, Ankit Patel

Master's Projects

Decompiling is an area of interest for researchers in the field of software reverse engineering. When the source code from a high-level programming language is compiled, it loses a great deal of information, including code structure, syntax, and punctuation.
The purpose of this research is to develop an algorithm that can efficiently decompile assembly language into pseudo C code. There are tools available that claim to extract high-level code from an executable file, but the results of these tools tend to be inaccurate and unreadable.
Our proposed algorithm can decompile assembly code to recover many basic high-level programming structures, including …

An Executable Packer, Neel Bavishi

Master's Projects

This thesis addresses the topic of development and advancement of the Packer technology. It aims to prove that with the implementation of advanced code encryption and cryptographic techniques in conjunction with standard packing
methods, testing binaries with anti-virus will become increasingly difficult.
Study on this topic reveals that the idea of encoding data has already been established, but it is still not fully incorporated into a technique to pack an executable file. There are some noticeable defects as un-packer tools have also made a great advancement in the field of dynamic analysis. The addition of new capability to recognize emulation …