280798
Instance-Dependent Verifiable Random Functions and Their Application to Simultaneous Resettability
We introduce a notion of instance-dependent verifiable random functions(InstD-VRFs for short). Informally, an InstD-VRF is, in some sense, a verifiable random function [23] with a special public key, which is generated via a (possibly)interactiveprotocol and contains an instance y? L? {0,1}*for a specific NP language L, but the security requirements on such a function are relaxed: we only require the pseudorandomnessproperty when y? Land only require the uniquenessproperty when y? L, instead of requiring both pseudorandomness and uniqueness to hold simultaneously. We show that this notion can be realized under standard assumption. 
 
Our motivation is the conjecture posed by Barak et al.[2], which states there exist resettably-sound resettable zero knowledge arguments for NP. The instance-dependent verifiable random functions is a powerful tool to tackle this problem. We first use them to obtain two interesting instance-dependent argument systems from the Barak's public-coin bounded concurrent zero knowledge argument [1], and then, we 
 
 1 Construct the first(constant round) zero knowledge arguments for NP enjoying a certainsimultaneous resettability under standard hardness assumptions in the plain model, which we call bounded-class resettable ZK arguments with weak resettable-soundness Though the malicious party (prover or verifier) in such system is limited to a kind of bounded resetting attack, We put NO restrictions on the number of the total resets made by malicious party. 
 1 show that, under standard assumptions, if there exist public-coin concurrent zero knowledge arguments for NP, there exist the resettably-sound resetable zero knowledge arguments for NP.
29420806
Strengthening QIM-Based Watermarking by Non-uniform Discrete Cosine Transform
Being extremely precise and at a low loss of perceptual quality, the attacks of value modification and optimized noise reduction still threaten the watermarking based on quantization index modulation (QIM). To resist them, the paper constructs a non-uniform discrete cosine transform (NDCT), and brings out an NDCT-QIM watermarking scheme, which embeds a watermark in a private NDCT domain with the parameters of NDCT as a secret key. The technique blinds the value modification by dispersing the attacking signal and changing its energy in the embedded domain. Because of the variable power spectrum of a watermark, the noise reduction becomes non-optimal. Some other advantages, including the ease of embedding, computational simplicity, etc., can also be acquired or maintained by the use of NDCT.
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.
44542461
An architecture for operating system support of distributed multimedia systems
Distributed multimedia applications introduce new design challenges at all systems levels from network protocols and operating systems to application support platforms. The paper describes an object-oriented architecture integrating network services with the operating system to support distributed multimedia systems. The architecture, called Dynamic Object Architecture (DOA), is based on Open Distributed Processing (ODP), the international standard on distributed system and client-server architecture. DOA utilizes object-oriented technology to address the requirements of distributed multimedia systems such as continuous media, natural synchronization, dynamic Quality of Service (QoS) and group communication. The architecture also provides a path using mature industry standards to develop new applications while retaining compatibility of old applications.
12262690
Communication Model to Support Rapid Application Development
Communication systems, along with database systems, have attracted a lot of attention in software engineering research. Encouraged by the success of SQL systems, some early efforts have been devoted to the study of a similar system for communication systems. Even though there has been some research to provide a common language or a virtual machine for building communication systems, there are only few theoretical studies on the complexity of specifying and modeling communication systems. In this paper, we propose an approach to model common communication systems which have no complicated stochastic control logics. Our model contains two parts: (1) a communication logic definition and (2) a set of communication system operations. Our approach has the following benefits: a unified interface between communication roles/systems, a recursive way to model communication systems, and the adoption of a multicastconference model. These benefits enable us to efficiently build scalable communication systems. Also, it enables us to provide a Graphic User Interface for users to build a customized communication system. We give a case study showing that our approach is effective and efficient in modeling common communication systems.
30407300
A G-Net Model for Knowledge Representation and Reasoning
The G-net model for G-type knowledge representation is introduced. It is capable of modeling both static semantic knowledge and dynamic control knowledge, combining them into a loosely coupled, mixed-type knowledge hierarchy. Four reasoning algorithms for the G-net model are proposed: inheritance reasoning and recognition reasoning for semantic knowledge, event-driven reasoning for dynamic knowledge, and control table reasoning for coordination and control in a mixed-type knowledge hierarchy. Based on the knowledge-table representation, the G-net model expresses the constraints and relationships among knowledge objects explicitly so that reasoning algorithms can be implemented efficiently. Applications to information systems prototyping are discussed. >
15968998
A formal approach for architectural modeling and prototyping of distributed real-time systems
For complex software systems, a central design concern is the system architecture. The systematic treatment of architectural specification and refinement is a proper basis for an engineering approach to system design. However, conventional Petri net models do not provide adequate abstractions for architectural specification, because their primary concern is behavior modeling and analysis. As an attempt to address this problem, we present a formal model called NOAM (Net-based and Object-based Architectural Model) for architectural specification and prototyping of real-time distributed systems. Building on the existing contributions from Petri nets, NOAM not only supports precise specification of real-time behavior embodied in a system architecture, but also provides a framework for systematic architectural refinement and exploration. Special focus is placed on using the formal model and our support environment to prototype NOAM specifications, and to meet real-time constraints.
44861778
Formal Analysis of Real-Time Systems with SAM
The Software Architecture Model (SAM) is a general software architecture model based on a dual formalism combining Petri nets and temporal logic. This paper proposes a formal method for modeling and analyzing real-time systems with SAM. A high level Petri net and a linear time temporal logic are used as the theoretical basis for SAM. Behaviors of real-time systems are modeled by Petri nets, while their properties are specified by temporal logic. By translating Petri nets into clocked transition systems, we can apply the Stanford Temporal Prover to automating the analysis of real-time systems. A case study of interactive multimedia documents demonstrates our approach to modeling and analyzing real-time systems with SAM.