35219345
Integrated architectural modeling and analysis for high-assurance command and control system design
A real-time architectural specification (RAS) approach and its application to command and control (C2) systems are presented. The objective is to establish a formal foundation that will enable us to integrate existing rich but fragmented formal techniques for system specification and verification into practical and scaleable formal engineering methods to support the design and development of highly reliable real-time distributed systems. The contribution of RAS is twofold; first, it provides a formal system that integrates the system's timing requirements and the propagation of the requirements into the process of architectural modeling and design and provides a systematic way to enforce that the requirements are met in every step of the design process. Second, it offers an incremental and more scalable approach for design modeling. These two features together make RAS a suitable model for the design of C2 systems. Based on these features, we further present an incremental method for verifying timing properties of a RAS model that helps to reduce the complexity of analysis both at a given design level or across different design levels.
9746543
Design an Interoperable Mobile Agent System Based on Predicate Transition Net Models
Mobile agents provide an effective and flexible style to develop advanced distributed systems. In order to promote interoperability and ensure the quality of mobile agent systems, it is necessary to formalize software architecture of mobile agent systems. In this paper, we not only define the software architecture of interoperable mobile agent systems using predicate transition nets, but also analyze the interoperability between agents. In addition, a formal model-driven design method to develop mobile agent systems is described with examples. Our method naturally integrates formal methods and practical approaches in the agent system design phase. The method can be used to develop other complex software systems as well.
10829689
A Framework for the Modeling and Prototyping of Distributed Information Systems
The major issues in designing Distributed Information Systems (DIS) include localization of control and data, inherent concurrency, intensive interactions among computation agents, history sensitivity, dynamic configuration and continuous system change and evolution. We propose a framework, called the G-Net model, for the specification, modeling and prototyping of DIS. The G-Net model not only provides a flexible notation to represent the executable specification of DIS through G-Net instantiation, but also offers a novel style of decentralized concurrent computation, allowing flexible inter-agent communication and interaction. A prototype of the G-Net framework has been implemented on workstations connected by a local network.
2725088
Architecture-driven modeling of real-time concurrent systems with applications in FMS
Abstract Petri nets have become increasingly popular for flexible manufacturing systems (FMS) modeling and control because they accurately capture the concurrent, non-deterministic and time-dependent properties of the systems. While offering many advantages, conventional Petri net models suffer from some serious problems that limit their usability as design models for complex FMS. Central to these problems is the lack of an engineering support for incremental design, refinement, and analysis of large-scale systems. In this paper, we present an architecture-driven approach for the modeling and design of FMS that effectively addresses the problems while leveraging the strengths of Petri nets. The approach has two major aspects: The first is a Net-based and Object-based Architectural Model (NOAM) that introduces a well-founded architectural framework into the Petri nets notation and lays a foundation to support formal design. The second is a modeling method based on NOAM that uses architecture decomposition and refinement as the basis to reduce design complexity, to provide smooth transition from informal to formal design, and to support incremental refinement and analysis. A case study using NOAM for FMS modeling is provided to show the applicability of our approach.
24822225
Achieving a Better Middleware Design through Formal Modeling and Analysis
13531819
A visual approach to XML document design and transformation
This paper presents a visual approach to the representation and validation of multimedia document structures specified in XML and transformation of one structure to another. The underlying theory of our approach is a context-sensitive graph grammar formalism. The paper demonstrates the conciseness and expressiveness of the graph grammar formalism. An example XML structure is provided and its graph grammar representation, validation and transformation to a multimedia representation are presented.
207129991
Guest Editors' Introduction - Best Papers from SEKE'98
2501651
A Fast Line Segment Based Dense Stereo Algorithm Using Tree Dynamic Programming
Many traditional stereo correspondence methods emphasized on utilizing epipolar constraint and ignored the information embedded in inter-epipolar lines. Actually some researchers have already proposed several grid-based algorithms for fully utilizing information embodied in both intra- and inter-epipolar lines. Though their performances are greatly improved, they are very time-consuming. The new graph-cut and believe-propagation methods have made the grid-based algorithms more efficient, but time-consuming still remains a hard problem for many applications. Recently, a tree dynamic programming algorithm is proposed. Though the computation speed is much higher than that of grid-based methods, the performance is degraded apparently. We think that the problem stems from the pixel-based tree construction. Many edges in the original grid are forced to be cut out, and much information embedded in these edges is thus lost. In this paper, a novel line segment based stereo correspondence algorithm using tree dynamic programming (LSTDP) is presented. Each epipolar line of the reference image is segmented into segments first, and a tree is then constructed with these line segments as its vertexes. The tree dynamic programming is adopted to compute the correspondence of each line segment. By using line segments as the vertexes instead of pixels, the connection between neighboring pixels within the same region can be reserved as completely as possible. Experimental results show that our algorithm can obtain comparable performance with state-of-the-art algorithms but is much more time-efficient.
207130140
Guest Editors' Introduction: Special Issue on Embedded Software Engineering
Embedded systems, typically components of larger electro-mechanical systems with the purpose of controlling or helping such systems to achieve their overall goals, are playing an increasingly critical role in modern society and economy. According to David Tennenhouse, Chief Scientist of Intel and former director of DARPA ISO, 98% of all current computer applications are embedded systems. The market for embedded computer applications has shown explosive growth with tremendous applications in, for example, telecommunications, health-care, manufacturing, remote monitoring, and transportation, to name a few. An important trend is that embedded systems are becoming increasingly complex, software-intensive and distributed. For instance, it was projected that software written for cellular phones will reach from 2 to 5 million lines of code in the next few years. While this underscores the growing importance of software it also raises some concerns since methods of developing embedded software are lagging far behind hardware advances. The unique characteristics of embedded systems, such as complex control logic, severe limitations on resources (e.g. memory and power consumption), hard real-time constraints, and stringent performance and dependability requirements, are stressing the limits of mainstream architectures, languages, tools, and techniques. Much of the embedded software development today depends on intensive manual programming and costly yet error-prone testing methods for quality assurance. Further, current embedded software development techniques use monolithic designs which are not scalable, configurable, or adaptable. These problems have resulted in long product cycles, cost overruns, and poor system quality. These problems, if not addressed, will escalate, and significantly hinder the development and deployment of complex embedded systems. This special issue on embedded software engineering is aimed at stimulating research interests in this important emerging area, which merges software engineering methodologies and techniques with embedded system development techniques. After careful reviews, five papers were selected for the special issue. Collectively,
42696276
Concurrently Non-malleable Black-Box Zero Knowledge in the Bare Public-Key Model
In this paper we study the possibility of reducing the setup assumptions under which concurrent non-malleable zero knowledge protocol can be realized. A natural model choice is the bare public-key (BPK) model of [6], a model with very minimal setup assumptions. Our main contribution is to show in this model the following about constant-round concurrent non-malleable black-box zero-knowledge arguments. 
They can be constructed from any one-way function for any language in $\mathcal{NP}$. Here, our construction takes 5 rounds, and we can reduce it to a 4-round (round-optimal) argument under existence of one-way permutations. 
Under number-theoretic assumptions, they admit a time-efficient instantiation for some specific $\mathcal{NP}$ languages (e.g., all languages having efficient Σ protocols, for which we can implement our construction using only $\mathcal{O}(1)$ modular exponentiations). 
 
 
 
Compared to the non-black-box construction in a concurrent work of [OPV, ICALP 2008] in this model, our protocol (even the construction from one-way function) is significantly more time- and round-efficient and can be based on more general assumptions.
26482984
Resettable Zero Knowledge with Concurrent Soundness in the Bare Public-Key Model under Standard Assumption
In this paper we present the firstconstant round resettable zero knowledge arguments with concurrent soundness for $\mathcal{NP}$ in the bare public-key (BPK for short) model assuming only collision-resistant hash functions against polynomial-timeadversaries. This resolves the problem whether there exist such protocols for $\mathcal{NP}$ in BPK model without assuming sub-exponential hardness. In our protocol, the resettable zero knowledge is demonstrated via a black-box simulator, while the concurrent soundness is proved by using the malicious prover strategy in non-black-boxmanner.