Abstract: The present disclosure provides a risk assessment method of water inrush in tunnels constructed in water-rich grounds. The method includes the following steps: simulating a tunnel excavation process by finite element software MIDAS GTS NX and fluid-structure interaction; according to a research method of control variables, analyzing effects of a groundwater level, an elastic modulus and advanced pipe shed grouting on the stability of surrounding rock, and improving an algorithm of a radial basis function (RBF) neural network using a Grey Relation Analysis (GRA)-based Partitioning Around Medoid (PAM) clustering algorithm to assess risks of water inrush occurring in Qingdao area.

Abstract: The present disclosure provides a multi-factor quantitative analysis method for deformation of a neighborhood tunnel. The method includes the following steps: analyzing monitoring data generated at a tunnel site; simulating collapse occurring at a shallow buried section of a tunnel; determining the degree of influence of each factor on the tunnel and a stratum; and determining quantitative influence of each factor on tunnel deformation. The present disclosure can not only provide an accurate theoretical basis for the construction of the shallow buried section of the small-distance tunnel, but also guarantee safety and cost saving during tunnel construction.

Abstract: Provided is engineered microorganisms expressing acetoacetyl-CoA reductase variants and a method for improving the yield of PHA. Compared with the wild-type acetoacetyl-CoA reductase represented by SEQ ID NO. 31, the variant has one or more of the following mutations: (1) mutation of valine at position 141 to isoleucine or leucine; (2) mutation of methionine at position 12 to threonine, serine, alanine, leucine, lysine or isoleucine; (3) mutation of isoleucine at position 194 to valine, leucine or methionine; (4) mutation of glutamic acid at position 42 to lysine, glutamine, leucine, aspartic acid, proline, threonine, asparagine, or histidine; and (5) mutation of phenylalanine at position 55 to valine, alanine or isoleucine. The variants and their coding genes can promote the synthesis and accumulation of PHA by the strain and increase the yield of PHA.

Abstract: A method for avoiding loop in an Ethernet ring includes, preventing, by transmit nodes constituting a ring, themselves from using the data frame transmission capabilities of ports on a link affected by a failure, when the ring failure has been detected by a transmit node constituting a ring; obtaining, by a master node of the ring, the ring failure, and performing a protection switching operation; flushing, by transmit nodes, their own forwarding tables, and forwarding a frame according to the flushed forwarding tables. If the failure in the ring has been removed, the master node shifts to a normal state and transmit nodes restore their data frame transmission capabilities of ports on a link ever affected by a failure. A system and an apparatus for avoiding data loop in an Ethernet ring are also disclosed.