Real-time software specification and validation with Transnet

The paper presents the executable specification method for real-time (embedded) systems Transnet. The method is based on an extension to Petri nets. A specification is developed by a problem decomposition into a set of parallel processes. Each process is defined by an extended Petri net with functions assigned to transitions, and conditions and time constants assigned to arcs. It is shown that Transnet matches with the characteristics of the intended class of applications. The available specification languages and the internal representation of data which describe the functional as well as nonfunctional requirements are outlined. The advantages of the Petri net-based representation and the possibilities of automatic net analysis and early validation are discussed.     

Constructive protocol specification using Cicero

This paper describes Cicero, a set of language constructs to allow constructive protocol specifications. Unlike other protocol specification languages, Cicero gives programmers explicit control over protocol execution, and facilitates both sequential and parallel implementations, especially for protocols above the transport-layer. It is intended to be used in conjunction with domain-specific libraries, and is quite different in philosophy and mode of use from existing protocol specification languages. A feature of Cicero is the use of event patterns to control synchrony, asynchrony, and concurrency in protocol execution, which helps programmers build robust protocol implementations. Event-pattern driven execution also enables implementers to exploit parallelism of varying grains in protocol execution. Event patterns can also be translated into other formal models, so that existing verification techniques may be used     

Software specification using graph grammars

The following paper demonstrates that programmed sequential graph grammars can be used in a systematic proceeding to specify the changes of high level intermediate data structures arising in a programming support environment, in which all tools work in an incremental and syntax-driven mode. In this paper we lay stress upon the way to get the specification rather than on the result of this process. Therefore, we give here some approach to “specification engineering” using graph grammars. This approach is influenced by the syntactical definition of the underlying language for Programming in the Small, the module concept etc. to be supported on one side but also by the idea of the user interface.     

Real-time tracking using trust-region methods

Optimization methods based on iterative schemes can be divided into two classes: line-search methods and trust-region methods. While line-search techniques are commonly found in various vision applications, not much attention is paid to trust-region ones. Motivated by the fact that line-search methods can be considered as special cases of trust-region methods, we propose to establish a trust-region framework for real-time tracking. Our approach is characterized by three key contributions. First, since a trust-region tracking system is more effective, it often yields better performances than the outcomes of other trackers that rely on iterative optimization to perform tracking, e.g., a line-search-based mean-shift tracker. Second, we have formulated a representation model that uses two coupled weighting schemes derived from the covariance ellipse to integrate an object's color probability distribution and edge density information. As a result, the system can address rotation and nonuniform scaling in a continuous space, rather than working on some presumably possible discrete values of rotation angle and scale. Third, the framework is very flexible in that a variety of distance functions can be adapted easily. Experimental results and comparative studies are provided to demonstrate the efficiency of the proposed method.     

Lucid Data Dreaming for Video Object Segmentation

International Journal of Computer Vision - Convolutional networks reach top quality in pixel-level video object segmentation but require a large amount of training data (1k–100k) to deliver...     

Testing correct model specification using extreme learning machines

Testing the correct model specification hypothesis for artificial neural network (ANN) models of the conditional mean is not standard. The traditional Wald, Lagrange multiplier, and quasi-likelihood ratio statistics weakly converge to functions of Gaussian processes, rather than to convenient chi-squared distributions. Also, their large-sample null distributions are problem dependent, limiting applicability. We overcome this challenge by applying functional regression methods of Cho et al. [8] to extreme learning machines (ELM). The Wald ELM (WELM) test statistic proposed here is easy to compute and has a large-sample standard chi-squared distribution under the null hypothesis of correct specification. We provide associated theory for time-series data and affirm our theory with some Monte Carlo experiments.     

Detection of metamorphic computer viruses using algebraic specification

This paper describes a new approach towards the detection of metamorphic computer viruses through the algebraic specification of an assembly language. Metamorphic computer viruses are computer viruses that apply a variety of syntax-mutating, behaviour-preserving metamorphoses to their code in order to defend themselves against static analysis based detection methods. An overview of these metamorphoses is given. Then, in order to identify behaviourally equivalent instruction sequences, the syntax and semantics of a subset of the IA-32 assembly language instruction set is specified formally using OBJ – an algebraic specification formalism and theorem prover based on order-sorted equational logic. The concepts of equivalence and semi-equivalence are given formally, and a means of proving equivalence from semi-equivalence is given. The OBJ specification is shown to be useful for proving the equivalence or semi-equivalence of IA-32 instruction sequences by applying reductions – sequences of equational rewrites in OBJ. These proof methods are then applied to fragments of two different metamorphic computer viruses, Win95/Bistro and Win9x.Zmorph.A, in order to prove their (semi-)equivalence. Finally, the application of these methods to the detection of metamorphic computer viruses in general is discussed.     

Real-time motion blur using extruded triangles

Several algorithms have been introduced to render motion blur in real time by solving the visibility problem in the spatial-temporal domains. However, some algorithms render at interactive frame rates but have artifacts or noise. Therefore, we propose a new algorithm that renders real-time motion blur using extruded triangles. Our method uses two triangles in the previous frame and the current frame to make an extruded triangle then send it to rasterization. By using the standard rasterization, visibility determination is performed efficiently. To solve the occlusion between extruded triangles for a given pixel, we introduce a combination solution using a sorting in front-to-back order and bitwise operations in the spatial-temporal dimensions. This solution ensures that only non-occluded extruded triangles are shaded. We further improve performance of our algorithm using a coverage map.     

Real-time 3D registration using GPU

3D registration is a computer vision technique of aligning multi-view range images with respect to a reference coordinate system. Aligning range images is an important but time-consuming task for complete 3D reconstruction. In this paper, we propose a real-time 3D registration technique by employing the computing power of graphic processing unit (GPU). A point-to-plane 3D registration technique is completely implemented using CUDA, the up-to-date GPU programming technique. Using a hand-held stereo-vision sensor, we apply the proposed technique to real-time 3D scanning of real objects. Registration of a pair of range images, whose resolution is 320 × 240, takes about 60 ms. 3D scanning results and processing time analysis are shown in experiments. To compare the proposed GPU-based 3D registration with other CPU-based techniques, 3D models of a reference object are reconstructed. Reconstruction results of three different techniques in eight different scanning speed are evaluated.     

Design and specification of iterators using the swapping paradigm

How should iterators be abstracted and encapsulated in modern imperative languages? We consider the combined impact of several factors on this question: the need for a common interface model for user defined iterator abstractions, the importance of formal methods in specifying such a model, and problems involved in modular correctness proofs of iterator implementations and clients. A series of iterator designs illustrates the advantages of the swapping paradigm over the traditional copying paradigm. Specifically, swapping based designs admit more efficient implementations while offering relatively straightforward formal specifications and the potential for modular reasoning about program behavior. The final proposed design schema is a common interface model for an iterator for any generic collection     

Detection of metamorphic and virtualization-based malware using algebraic specification

We present an overview of the latest developments in the detection of metamorphic and virtualization-based malware using an algebraic specification of the Intel 64 assembly programming language. After giving an overview of related work, we describe the development of a specification of a subset of the Intel 64 instruction set in Maude, an advanced formal algebraic specification tool. We develop the technique of metamorphic malware detection based on equivalence-in-context so that it is applicable to imperative programming languages in general, and we give two detailed examples of how this might be used in a practical setting to detect metamorphic malware. We discuss the application of these techniques within anti-virus software, and give a proof-of-concept system for defeating detection counter-measures used by virtualization-based malware, which is based on our Maude specification of Intel 64. Finally, we compare formal and informal approaches to malware detection, and give some directions for future research.     

Software metrics using a metasystem approach to software specification

This article investigates how software metrics can be defined as part of a metasystem approach to the development of software specifications environments. Environment transformation language (ETL) is used to define metric computations. In our approach, metrics applicable to a particular specification environment (e.g., a data flow diagram environment) are defined in conjunction with a formal definition of that environment as given in environment definition language (EDL). The goal is to support a metric-driven approach to software development by incorporating, with relative ease, the metric computation into the software specification environment. As representative examples, metrics for data flow diagrams, structure charts, and resource flow graphs are described and analyzed. We demonstrate how an analyst, interacting with the system, can use metrics to improve the quality of the deliverables.     

Real-time grasping strategies using event camera

Journal of Intelligent Manufacturing - Robotic vision plays a key role for perceiving the environment in grasping applications. However, the conventional framed-based robotic vision, suffering from...     

Real-time stress assessment using thermal imaging

Thermal imaging is one of the most promising methods of probing the psychological status of human beings because of its non-invasiveness. This study develops a new method of assessing the stress status in real time. The differential energy between philtrum (located in the maxillary area) and forehead (DEFP) algorithm is developed to amplify and extract stress-induced thermal imprints. The algorithm is then validated against the clinical standard in a controlled lab experiment in which neurophysiologic responses are invoked from subjects via Trier Social Stress Test. The correlation between the extracted thermal imprints and established stress markers (heart beat rate and cortisol level) is significant. Experimental result demonstrates that DEFP has the capacity to classify stress and baseline status. An accuracy rate of over 90 % suggests the feasibility of the real-time assessment of stress, disregarding personal factors.     

Real-time pattern matching using projection kernels

A novel approach to pattern matching is presented in which time complexity is reduced by two orders of magnitude compared to traditional approaches. The suggested approach uses an efficient projection scheme which bounds the distance between a pattern and an image window using very few operations on average. The projection framework is combined with a rejection scheme which allows rapid rejection of image windows that are distant from the pattern. Experiments show that the approach is effective even under very noisy conditions. The approach described here can also be used in classification schemes where the projection values serve as input features that are informative and fast to extract.     

Real-time controllable fire using textured forces

Fluid dynamics can produce realistic looking fire effects, which are heavily used in animation and films. However, the parameters of the various underlying physical equations are not intuitive enough to be controlled easily. As a result, animators face problems when editing the fine details of the fire, especially the turbulence and growth at the fire surface. In this paper, we propose a new approach to enable animators to interactively edit such fine details using textured forces. These techniques involve mapping a texture onto the simulation that controls the creation of new forces, growing the fire into specific shape and adding the natural turbulence of fuel ignition. These textures can be edited using an intuitive user interface that allows forces to be painted directly onto the fire. Our system can be integrated into existing GPU fluid solvers to run in real-time. As a result, it is applicable for interactive applications such as 3D computer games.     

Real-time hand detection using continuous skeletons

In this paper, a fast and reliable method for hand detection based on continuous skeletons approach is presented. It demonstrates real-time working speed and high detection accuracy (3–5% both FAR and FRR) on a large dataset (50 persons, 80 videos, 2322 frames). These make it suitable for use as a part of modern hand identification systems including mobile ones. Overall, the study shows that continuous skeletons approach can be used as prior for object and background color models in segmentation methods with supervised learning (e.g., interactive segmentation with seeds or abounding box).     

Formal interaction specification in public health surveillance systems using pi-calculus

This paper provides formal specification of interactions in typical public health surveillance systems involving healthcare agencies at local, state and federal levels. Although few standards exist for exchange of healthcare information, there is a general lack of formal models of the protocols involved in the interactions between the agencies. The quality of medical care provided is an end result of a well designed choreography of diverse services provided by different healthcare entities. One of the major challenges in this field appears to be explicit formal specification of such interactions. Such formal specification work is the first step leading to both design and verification of important properties of public healthcare systems. pi-calculus is a formal modeling technique for precise specification of semantics in interacting concurrent systems where mobility is involved. Two different configurations of public health surveillance systems are modelled using pi-calculus in this paper.