This work presents a static-analysis based method for analyzing the robustness of a given embedded control system design, in the presence of quality-faults in sensors, software components, and inter-connections. The method characterizes the individual components of the system by storing the relations between the precision of inputs and the precision of outputs in what we call, lookup tables (LUTs). A network of LUTs thus formed which represent the given control system is converted into a satisfiability modulo theory (SMT) instance, such that a satisfying assignment corresponds to a potential counterexample (the set of quality-faults which violate the given fault-tolerance requirements) or hot-spot in the design. Hot-spots obtained in this manner are counter-verified through simulation to filter the false-positives. Experimental results on the fault-tolerant fuel controller from Simulink automotive library demonstrate the efficacy of the proposed approach.

The objective of this research is to develop to the proof-of-concept stage, a fault tolerant diagnosis system for the RADARSAT-1 attitude control system (ACS) telemetry. The proposed system is using computational intelligence (CI) to detect and isolate faults and also to infer cause of failures from the telemetry data time series history using functional models of satellite ACS. The proposed work is based on a distributed nonlinear, self-learning and self-adapting models (that can learn and improve themselves overtime) adjusting to the environment and constraints to which the real data is subjected. The key research and development issue is to create prototype models that will be able to integrate telemetry data and address the fault diagnosis problem without human intervention and expertise. The proposed work aims to support space industries' future interests in on-board fault diagnosis for next generation spacecraft by utilizing CI techniques as well as to help ground system operators in performing calibrations, anomaly detection, isolation and recovery, or testing of components.

Traditional approaches of executing complete system test suite to validate software systems on deploying the upgrades of commercial off-the-shelf (COTS) software components is typically costly and time-consuming, resulting in delay in deploying the upgrades. In this paper, we present a process that examines the test case dependencies at finer granularity level of altered-functions in the upgrades of COTS software and recommends a smaller regression test suite. The process captures and analyzes the functional-level runtime interactions among the applications and COTS components to find the impact of the upgrades on the system. The process includes a procedure to identify the altered-functions in a component. We have developed a prototype based on the concepts proposed in the paper and performed a case study on a web-based application to illustrate efficacy of the prototype. The results of the case study show that up to 80% reduction in regression test efforts could be achieved.

In a PC based Network Intrusion Detection System (NIDS), the packet capturing component is a key bottleneck which reduces its effectiveness. NIDS deployment on multiprocessor or distributed systems that circumvents this bottleneck do not address operating system performance limitations which are the causal factors behind this bottleneck. Completion of intrusion detection task in bounded time at the sensors is also important to detect complex and co-ordinated attack patterns. Existing Linux based packet capturing solutions, NAPI and PFRING, are inefficient and have poor real-time performance. We have implemented an user space network interface (DMA ring) to capture packets under high network load on a modest commodity platform. DMA ring outperforms existing solutions in terms of higher load bearing, packet capturing capacity and superior real-time behavior. We proposed a scheme using DMA ring, which will improve the performance of an user space NIDS.

Establishing the correctness of reliable distributed protocols supporting critical applications necessitates modular/compositional approaches to tackle the inherent complexity of these protocols. Efforts involved in the specification and verification of these reliable distributed protocols can be considerably reduced if the protocol is composed utilizing smaller components (building-blocks) possessing individual functionalities that are integral parts of the overall protocol operation. In this paper we present the modular composition of a transaction processing protocol, namely the three-phase commit (3PC) protocol utilizing concepts of category theory. Specifically, we illustrate how the overall global properties of the protocol can be proved by utilizing constructs of local sub-properties of the inherent building blocks of the 3PC protocol.

The mission-critical and dependability aspects of autonomous systems demand formal level of assurance in ascertaining their mission-survivability capabilities. The complete understanding of system autonomy and its verification and validation (V&V) continue to pose technical challenges. In recent years, formal methods have shown considerable promise in the area of V&V of autonomous systems. In this paper, we further explore the applicability of model checking techniques in run-time verification of autonomy software such as automated planning and scheduling algorithms. We illustrate our proposed approach for runtime verification through a case study of FireSat satellite. We also discuss our experiences and ongoing research activities in this direction.

In recent years, formal methods (FMs) have been extensively used for the verification and validation (V&V) of dependable distributed protocols. In our studies utilizing FMs for V&V, we have observed that a number of protocols providing for distributed and dependable services can often be formulated using a small set of basic functional primitives or their variations. Thus, from the formal viewpoint, the objective of this paper is to introduce techniques, utilizing concepts of category theory, that could effectively identify and reuse basic formal modules in order to simplify formal specification and verification for a spectrum of protocols.

The effective design of composite dependable and real time protocols entails demonstrating their proof of correctness and, in practice, the efficient delivery of services. We focus on these aspects of correctness and efficiency, specifically considering the real time aspects where the need is to ensure satisfaction of stringent timing and operational constraints. We establish the use of mathematically rigorous techniques such as formal methods (FMs) in not only providing for their traditional usage in establishing correctness checks, but also for their capability of assessing and analyzing timing requirements in dependable real time protocols. We present our perspectives in utilizing FMs in developing exact case analyses of fault tolerant and real time protocols. We discuss the insights obtained and flaws identified in the hand analysis over the process of formally analyzing and verifying the correctness of an existing fault tolerant real time scheduling protocol.

A general paradigm for lifting binary morphological algorithms to fuzzy algorithms is employed to construct fuzzy versions of classical binary morphological operations. The lifting procedure is based upon an epistemological interpretation of both image and filter fuzzification. Algorithms are designed via the paradigm for various fuzzifications and their performances are analyzed to provide insight into the kind of liftings that produce suitable results. Algorithms are discussed for three image processing tasks: shape detection, edge detection, and clutter removal. Detailed analyses are given for the effect of noise and its mitigation owing to fuzzy approaches. It is demonstrated how the fuzzy hit-or-miss transform can be used in conjunction with a decision procedure to achieve word recognition.

A complex application consists of a set of software modules, executed on a distributed system, guided by requirements imposed by the designer and the system. The REAL project at NJIT has been investigating the resource allocation problem for such a system. We give a classification of and syntax for constraints, provide a rule-based approach for constraint management, and discuss issues in generating implied constraints and consistency checking.