Xing Pan

Modeling and simulation for SoS based on the DoDAF framework

On the basis of analyzing the products and views in DoDAF (Department of Defense Architecture Framework), an integrated framework on modeling and simulation for SoS (System of Systems) is proposed. A modeling approach based on the DoDAF which uses ABM (Activity Based Methodology) for SoS is presented. Via SysML (Systems Modeling Language) the operational views of the model can be transferred into the dynamic executable model of BPMN (Business Process Modeling Notation). By giving the clock parameters for the dynamic model, the model above can be used to simulate, inspect and verify SoS under typical environments and conditions. Then, a case of the SoS on civil aviation airline transportation is given to illustrate the application of the proposed model and method.

Systems thinking: A comparison between Chinese and western approaches

Abstract This paper presents a comparison between Chinese perspectives on systems thinking and ideas from the West, primarily the U.S. and the U.K. In particular we focus on the debate between reductionism and holism which is one of the classical subjects of study in the philosophy of science. Just like the West, China experienced theoretical debate between holism and reductionism which spanned across a broad range of fields such as traditional Chinese medicine and reliability-centered systems engineering. The Chinese developed their own oriental systems methodologies based on the philosophical foundation of ancient oriental philosophy thoughts and dialectic principle, the most distinctive of which include the Meta-synthesis Approach and the Wuli - Shili - Renli approach. In the Western approach to systems thinking there are similar concepts of holistic thinking, synergism, and cause and effect. However, interesting differences exist between China and the West in the role of intuition in decision making. We explore these differences and discuss the implications for applying each approach in different problem solving contexts.

A Review of Cognitive Models in Human Reliability Analysis

Human error behavior is determined by both environmental and human factors. In particular, psychological and spiritual factors have a decisive impact on human errors. The human cognitive model not only makes a sound exposition of the generation process and mechanism of human erroneous actions but also improves the accuracy and credibility of human reliability analysis (HRA). Therefore, it helps effectively avoid and prevent human errors in industrial fields. This paper highlights the significant role that the cognitive model has played in HRA. Then, based on an analysis of the nature of human behavior and the classifications of common human errors, several typical cognitive models are summarized in the areas of ergonomics, behavioral science, and cognitive engineering, including a cognitive model related to process, an information-processing model, a decision-making and problem-solving process model, and a cognitive simulation model based on computer technology. Then, cognitive models and the corresponding HRA methods that are applied in the fields of reliability engineering, safety engineering, and risk assessment are reviewed. Finally, some directions and challenges are proposed for the future research of cognitive models applied in HRA methods based on the discussion of current cognitive models used in HRA methods. Copyright

A fuzzy synthetic evaluation method for failure risk of aviation product R&D project

There are many risk factors which lead to the failure of aviation product R&D project, and usually, technical risk, cost risk and schedule risk are three primary kinds of risk. According to failure risk analysis in aviation product R&D project, a risk breakdown structure (RBS), including risk factors and risk consequences, is proposed. More over a fuzzy synthetic evaluation method based on probability risk analysis (PRA) method integrated with fuzzy AHP method used triangular fuzzy numbers is presented to evaluate the failure risk of aviation product R&D project. The method is more available and effective to evaluate the risk which is difficult to give the value and the weight of indexes. At last, a case of aviation R&D project failure risk evaluation is given to illustrate the application of the proposed method.

Organizational Reliability Capability Assessment: A Case Study in China R&D Enterprise for Aviation Products

The IEEE Standard 1624 provides a foundation for the assessment of organizational reliability capability (ORC). However, to better match the individual characteristics of different industries, this standard needs to be suitably clipped and adjusted, so as to develop customized models for the reliability capability evaluations of different organizations. To evaluate the ORC of Chinas aviation enterprises effectively, we propose a reliability engineering capability maturity model (RE-CMM) for Chinas aviation industry, with adequate consideration of the features closely associated with Chinas aviation enterprises and Chinas military standards. The proposed RE-CMM model is established on the theoretical basis of Capability Maturity Model Integration (CMMI), combined with the IEEE standard and Chinas military standards for Reliability, Maintainability, and Supportability (RMS). Structural equation modeling (SEM) is used to verify the validity of the RE-CMM model. We use a fuzzy method for the evaluation of reliability engineering capability. Detailed steps of reliability engineering capability assessment are also provided for the application of the model. Finally, a case study on a Chinese aviation enterprise is given to illustrate the model and method.

Research of organizational RMS engineering capability assessment method

The effective assessment of organizational reliability, maintainability and supportability (RMS) engineering capability has an important significance to improving organizational RMS work level. For the problem of organizational RMS engineering capability assessment being complex, and many indexes being fuzzy and difficult to be defined the value and weight, a method based on fuzzy analytic hierarchy process (FAHP) was proposed to assess organizational RMS engineering capability. Firstly, the concept of organizational RMS engineering capability was defined and the index system for RMS engineering capability assessment was presented. Secondly, concrete steps of organizational RMS engineering capability assessment method based on FAHP for application of the system were introduced. Finally, the application of a case was given to verify the method effectively.

Influence of work motivation and task difficulty on human reliability

The human reliability analysis (HRA) has long been focusing on determining causes of human error. Most current HRA studies concentrate on the influence of external context factors, such as working conditions, task time, etc., on human performance while ignoring internal psychological factors, for example, personality characteristics, feelings, motivations and so on. To explore both internal and external factors impact on human reliability, we designed an experiment measuring the effects of work motivation, task difficulty on human error probability (HEP). 120 subjects participated in the experiment. The task difficulty levels in the experiment are much depends on the subjects experience and training conditions. The results demonstrate that the general relationship between work motivation and HEP can be described by a U curve and the optimal work motivation is shifted with different task difficulty level, which also fit with Yerkes-Dodson Law.

Resilience-based optimization of recovery strategies for network systems

Network systems, such as transportation systems and water supply systems, play important roles in our daily life and industrial production. However, a variety of disruptive events occur during their life time, causing a series of serious losses. Due to the inevitability of disruption, we should not only focus on improving the reliability or the resistance of the system, but also pay attention to the ability of the system to response timely and recover rapidly from disruptive events. That is to say we need to pay more attention to the resilience. In this paper, we describe two resilience models, quotient resilience and integral resilience, to measure the final recovered performance and the performance cumulative process during recovery respectively. Based on these two models, we implement the optimization of the system recovery strategies after disruption, focusing on the repair sequence of the damaged components and the allocation scheme of resource. The proposed research in this paper can serve as guidance to prioritize repair tasks and allocate resource reasonably.

Relativity modeling of work motivation and human error probability based on neural network

Human error behavior is jointly determined by human and environment, specially, the effect of work motivation has been emphasized to be an important factor on human performance in psychology and behavioral science. However, current Human Reliability Analysis (HRA) pay little attention to this aspect, which creates difficulties in finding the mechanisms of error behavior that could arise in the cognitive process. To fill the gap mentioned above, this paper considered work motivation factors into HRA, the hypothesis of the relationship between work motivation and Human Error Probability (HEP) in task context was given, with reference to the relationship between arousal and performance described by Yerkes-Dodson Law in psychology, then a relativity model of work motivation and HEP on different task difficulty was proposed based on neural network, and simulation experiment was carried out. The experimental results showed the work motivation-HEP relationship is of a U-shaped curve and the optimal work motivation for a difficult task is lower than an easy task.

Area method used in the evaluation of resilience implementation approaches in system of systems

System of systems (SoS), like transportation systems and combat systems, is integrated by a set of independently operating systems that interact with each other to provide an end-to-end capability, which cannot be achieved by individual systems. Resilience is the ability of an SoS to recover to a desired performance level after disruptive events. Even though many measures have been proposed to evaluate resilience, there is no one general metric that can be used in all situations. Given that what we actually need is the performance process with time, this paper presents an area method to evaluate resilience by calculating the area below the performance curve after disruption. Meanwhile, we propose the SoS operating time, combined with the area method, to identify which of the recovered performance levels and the recovery speeds is more important according to different situations. Finally, the proposed research enables us to evaluate resilience implementation approaches and select the best one.