The tensile force,impact,fracture toughness,stress-corrosion,corrosive tension for the30CrMo used in the CNG steel tank in different quenching medium have been investigated in the paper.The results show that using the PAG quenching medium benefits decreasing the ratio ofσ s toσ b and increasing the security of CNG steel.The ration ofσ s toσ b and fracture toughness are the important parameters for evaluating security of CNG steel tank.
Abstract A novel method is proposed to characterize the multi-scale lamina structure in fine-grained sedimentary rocks using geophysical well logs. The low limit of individual lamina detection using geophysical well logs is improved to 2.5 mm through image log derived slab image and button conductivity curves. Lamina structure in terms of composition and texture of individual lamina as well as lamina assemblages are determined from core and thin section images. Fine-grained sedimentary rocks are divided into massive, layered and laminated according to core-scale lamina observation. Thin section observation reveals that the mineral composition of individual lamina includes carbonate, silt, clay mineral, tuffaceous lamina and organic matter lamina in the micrometer-scales. The lamina couplets (silt-organic, silt-clay, tuff-organic and carbonate-silt) or triplets (silt-clay-organic) can be classified according to the mineral assemblage. Static and dynamic image logs with 5 mm vertical resolution have low ability to capture the lamina assemblage. Therefore the slab images and button conductivity curves are generated from image logs to facilitate the recognition of laminae. The color patterns (dark-yellow-light-bright) and conductivity values (width of curves) of button conductivity curves can reflect the variations in composition and texture of individual lamina. Core and thin section are calibrated with slab images as well as button conductivity curves to build a method to recognize multi-scale lamina structure. This novel and multidisciplinary approach provides a powerful method for continuously identifying lamina structure with a 2.5 mm vertical resolution using well logs, and have theorical and practical implications for lamina investigation in fine-grained sedimentary rocks.
Various electronic equipments and control devices being used in the vehicle, the communication in network of different bus protocols becomes more important. This paper introduces a new method of conversion to achieve the ZigBee communication with CAN bus, realizing the link of CAN bus and wireless network. In order to conquer the illogicalities or conflictions brought from bus configuration and protocol of various controllers, Philips SJA1040A CAN transceiver and 32 bit MCU are used to constitute a CAN brainpower node, Freescale MC13202 ZigBee transceiver is integrated to manage the ZigBee wireless network, identifying the network topology and adding/removing the nodes. The system could realize data communication between the distributed ZigBee points and CAN bus fleetly and exactly, as well as simple configuration. This converter has certain applied value in intelligent control and user friendly design of car wireless.
Characteristics of wireless sensor network and working scenario of wireless communication great affect clustering topology and coverage performance, furtherly affect transmission reliability and robustness of the network. Biological immune algorithm is adopted to solve issues of clustering topology control and coverage optimization in wireless sensor network which is deployed by the static and mobilizable nodes. Immune Clustering and Coverage optimization algorithm (ICCO) is proposed which includes Immune Clustering optimization algorithm (ICIO) and Immune Coverage optimization algorithm (ICOO). Immune efficient clustering is done on the static senor nodes and hierarchical clustering topology control is established and optimized. Locations of mobile sensor nodes are dynamically adjusted by immune algorithm to realize the maximum value of coverage which is a multi-objective optimization issue. Mathematical model is established to analyze the performance of network including the convergence, energy consumption and area coverage. Simulations show that ICCO has realized the maximum coverage and robust topology with improved performance of fault tolerance by mobilizable nodes.
A new variable-step-size LMS algorithm is proposed, and it performance is analyzed. Simulation results indicate that the performance is superior to that of existing VSS algorithm and NLMS algorithm. The proposed algorithm is then applied to adaptive noise jamming cancellation system; the computer simulation shows superior performance over the NLMS algorithm and MVSS algorithm.
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