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The study aims to investigate the mechanical system optimum design based on collaborative theory. Due to the complexity of the modern machinery, mechanical systems are readily to damage when unexpected failures occur on important components. It is therefore, critical to monitor the machine state for preventing the impending faults. The key issues to realize the feasible and reliable mechanical condition monitoring is information acquisition, which relies on the available design of the detection devices. Literature review indicates that an extensive attention has been put on the so called Monitorability in the systematic design of mechanical systems. Monitorability is emphasized that in the original design of mechanical systems one should consider available information acquisition property. Moreover, monitorability-based design is known as a design attribute of mechanical system worldwide. However, less work has been done in this field. In this study, a novel method based on collaborative theory is proposed for the monitorability design. The connotation and application of collaborative theory for monitorability design are discussed in details. The information synergy model and organization framework of monitorability-based design are established by using computer technology and network technology. The experiments demonstrate the effectiveness of the proposed monitorability design system for a more powerful optimum design of mechanical systems and show a promising future for the industrial applications.

International audience; In the literature, research on pre-accident and post-accident analysis has been reported extensively. The former falls into the category of risk analysis to identify the potential hazards and the consequences, so that decisions can be made to take appropriate preventive and mitigation measures. The latter amounts to accident investigation for learning lessons and finding solutions. This paper uses the catastrophe of Cruiser Eastern Star in 2015 as a case study to analyze some typical accident models, including the Swiss Cheese Model, AcciMap, Stamp, FRAM, etc. By comparison, pros and cons of each perspective are identified. Overall common challenges for all methods are pointed out and a reflection is offered with respect to the added value of complementing the analysis under a resilience perspective, to enhance preparedness for unknown adverse events.

Ports are rally points and hubs of water and land transportation, important nodes of the internet of things as well, which are inevitably susceptible to surrounding meteorological environment. To address this issue, a comprehensive environment monitoring system with early warning and linkage control is presented in this paper. First, our system can monitor surrounding meteorological environment data in real-time, which ensures to provide early warming if there encounters any exception. Second, our system can be used to forecast future environment, which significantly benefits the operations and schedules of ports. The last but not the least, through linkage control with other relevant systems, our system enables to meet the needs of green port development. The framework of our system, together with the design of some main software modules, are described in details. Furthermore, several main characteristics and functionalities of our system are further thoroughly introduced.

In this paper, a tie-bar extension-force online monitoring system in a tie-bar arch bridge is presented. Optical fiber Bragg grating strain sensors are embedded in the tie-bar arch bridge for online monitoring of changes in the state of internal force. The relation between the tie-bar extension force measured by optical fiber Bragg grating strain sensors and the internal state of the tie-bar arch bridge under the actions of loading and temperature are discussed. The results show that the embedded optical fiber Bragg grating strain sensors can display the internal-force state of a tie-bar bridge and are a powerful and sensitive assistant that is convenient for and beneficial to engineers and that provides a great variety of options for avoiding disasters.

C+ ion beam-assisted deposition was utilized to prepare deposit diamond-like carbon (DLC) film. With the help of a series of experiments such as Raman spectroscopy, FT-IR spectroscopy, AFM and nanoindentation, the DLC film has been recognized as hydrogenated DLC film and its tribological properties have been evaluated. The ball-on-disc testing results show that the hardness and the tribological properties of the DLC film produced by C+ ion beam-assisted deposition are improved significantly. DLC film produced by C+ ion beam-assisted deposition is positive to have a prosperous tribological application in the near future.

Many researches indicate that a great number of failures occur in the tribological system which will reduce the reliability of the marine diesel engine. Therefore, it is necessary to monitor the condition and identify the fault mode of the engine. In this paper, remote fault diagnostic technology is developed to take full advantage of the online oil monitoring system and the laboratory analysis for the tribological systems. To increase the efficiency of fault diagnosis, a two-level fault diagnostic model based on self-organizing map (SOM) was established with the oil parameters from the online oil system and the experimental data from the laboratory. Based on the component map of SOM network, the attributes of the feature vector in the second level were reduced to simplify the model and the trajectory of the samples was tracked during the application of the system. The diagnostic result indicates that the remote fault diagnosis technology benefits the full acquirement of the information reflecting the engine condition and the two level fault diagnostic model can be well applied in fault diagnosis for the tribological systems in marine diesel engine with satisfactory result.