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Hydraulic turbine runners experience high excitation forces in their daily operations, and these excitations may cause resonances to runners, which may induce high vibrations and shorten the runner's lifetimes. Increasing the added damping of runners in water can be helpful to reduce the vibration level during resonances. Some studies have shown that the modification of the trailing edge shape can be helpful to increase added damping of hydrofoils in water. However, the influence of blade trailing edge shape on the added damping of hydraulic turbine runners has been studied in a limited way before. Due to the difficulties to study this problem experimentally, the influence of blade trailing edge shape on a Kaplan turbine runner has been studied numerically in this paper and the one-way FSI method was implemented. The performances of three different turbulence models, including the k − ϵ , k − ω SST , and transition SST models, in the added damping simulation of the NACA 0009 hydrofoil were evaluated by comparing with the available results of the two-way FSI simulation in the references. Results show that, unlike the significantly different performances in the two-way FSI method, the performances of all the turbulence models are very close in the one-way FSI method. Then, the k − ϵ turbulence model was applied to the added damping simulation of a Kaplan turbine runner, and results show that the modification of the blade trailing edge shape can be helpful to increase the added damping to some extent.

The study presents the design and fabrication process of a novel microfluidic active droplet generator and development of a controller to actuate the integrated micropumps. The proposed active droplet generator consists of a droplet generation geometry and two microfluidic pumps to control the flow rate of the continuous phase fluid and the dispersed phase fluid to generate a microflow towards the droplet generation geometry. The droplet generator is developed based on flow-focusing geometry. Proposed micropumps have a pump chamber and a reservoir. A layer by layer method is adapted in fabricating the active droplet generator in which Polymethyl Methacrylate (PMMA) is used as the material. A heat treating based bonding method is discussed in combining fabricated PMMA layers together. Piezoelectric transducer, which is used as the actuator, is made of Lead Zirconate Titanate (PZT) and integrated into the micropump geometry to produce the microflow. The developed controller is capable of providing a range of shapes, frequencies, and amplitudes for the input signal leading to successful operations of the active droplet generator.

The yarn break detection system of ring spinning based on tunnel magnetoresistance effect is proposed in the paper. The TMR element is used to detect the anomaly signal caused by rotating traveler. The signal reflects the rotation speed of traveler and the yarn break is monitored by speed measurement. The yarn break sensor, section detection module, machine monitoring module are designed and implemented. The performance test result indicates that the system can satisfy the practical application of yarn break detection with the advantages of compact size, high sensitivity, strong anti-interference capability and so on.

The diffusion equation describing the light transportation in two dimensional two layers dental model with finite size is solved by finite element method,and the optical intensity distribution inside the dental tissueis is obtained.The penetration depth is defined and analyzed when dental enamel and dentin is under different optical parameters.It is revealed that penetration depth decreases with the increase of scattering coefficient of dental enamel,but increases with the increase of scattering coefficient of dental dentin.In the case of variation Rate of penetration depth to scattering coefficient,dental enamel is much larger than dentin.And,the Monte Carlo random statistical method is used to verify the correct of solution of diffusion equation based on finite element method.

The complete pathological tooth model and the criterion of caries lesion extent are established.With the programme of Monte Carlo simulation algorithm,the process of fluorescence excitation and transmission in tooth tissue is completely simulated and the relationship between the changes of optical parameters caused by the tooth tissue lesions and fluorescence distribution of QLF ia also explored.And,the legitimacy of the process above is verified using fluorescent functional of tracepro software.With the increase of lesion extent in dental caries part,the results show that the difference of fluorescence distribution between healthy and diseased tissue are increased with the increase of scattering coefficient and the reduce of absorption coefficient and fluorescence quantum efficiency.

Large quantities of dangerous substances, especially explosive or flammable gases, are processed or stored in hazard installations. A risk-based warning/early-warning system for major hazard installations is very important for the prevention of major accidents. The real-time data-based risk and the risk factors are analyzed in this article, and a fuzzy logic based real-time risk assessment method is proposed. On the basis of fuzzy logic theory, the likelihood of an accident occurrence and the consequence of the accident can be assessed, and the risk value or risk level can be evaluated by utilizing a risk matrix. The method takes advantage of the real-time data acquired from the safety monitoring system so that the change in the risk can be determined as the accident develops. The risk assessment simulation of a vapor cloud explosion (VCE) accident caused by gas leaked from an liquefied petroleum gas tank is performed. It is shown that the risk of a VCE accident varies with the change of the monitored data. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008

Based on the investigation on the application situation about IT in the SMEs of Ningbo, the main problems about the informatization of the fastener manufacturing companies in Ningbo were systematically analyzed, which indicated that the government's guidance is essentially necessary. Then the conclusions were drawn on the principles and suggestions that the local government ought to follow in the process of guiding traditional fastener manufacturing companies to better utilize IT in the SMEs. Some concrete countermeasures this thesis proposed lastly included that: (1) the government ought to support and assist the clustering fastener manufacturing companies to make a informatization planning, (2) to guide the both the division and cooperation within the industrial clusters to enhance their core competitiveness, (3) to regulate the markets for equitable competition among the fastener manufacturing companies, (4) to initiate the mechanism of right human resources management and the special inspiration in order to accelerate the optimal transferring of intelligentsia in the fastener manufacturing companies, (5) to create the credit database of the SMEs to cultivate the credit intermediary agents, (6) to speed up to formulate the informatization standards for the industry in order to amplify the community information service system and improve the informatization infrastructure, (7) to carry forward the innovation in the companies with utilizing of IT, (8) to accelerate the developing of e-commerce in fastener manufacturing companies, (9) to strengthen the classified guidance for advancing this sector's structure.

Distributed and remote monitoring and control are important to manage the distributed major hazard installations and to keep people and properties from dangers. In the present paper, we propose the multi-agent group (MAG) model which involves 5 agents with complementary functions for monitoring and control of hazard installations. The distributed MAGs can achieve the distributed monitoring and control goal for hazard installations. The SNMP based structure of the Remote Communication Agent (RCA) is analyzed, based on which different monitoring modes can be established flexibly. The RCA controls the network communication traffic in an intelligent way, it learns from the environment and negotiates with other RCAs. Factors contributing to the periods of dynamic data transmitting are analyzed. During the monitoring and control process the data transmitting periods can be adjusted according to the change of environment.

The mechanism of accident prevention is similar to the hazard immunological recognition of the biological immune system. In a word, an enterprise (or industry park) is like an organism and the safety management system is similar to the biological immune system. Thus, safety management measures are the accident immune factors, which identify and manage the hazardous factors so as to avoid accidents. In this paper, the development of the preparation and application of the biological immune system in work safety management was reviewed, and the corresponding problems are discussed and forecasted. The author points out that the accident immune model based on the biological immune mechanism, which has the functions of assessment of danger immunological tolerance, prevention & early warning of accident, emergency response to accident, and rapid recovery after accident, is the main direction of current research.