Abstract: A method for preparing a shell-bionic ceramic tool and a shell-bionic ceramic tool, wherein the shell-bionic ceramic tool includes alternating stacks of ceramic powders with different components, pressing a ceramic green body using a cold briquetting method, carrying out pre-pressing once using a graphite indenter on a working surface thereof after each layer of the ceramic powder being loaded, and pressing a last layer using a graphite rod, and then pressing a whole ceramic green body with a certain pressure to promote a bonding of the layers of ceramic powder, which in turn gives a complex shape to an interface between the layers, increases a bonding area between the layers, and plays the role of hindering crack expansion, extending the crack expansion path, and improving the bonding strength of the interface; after then, hot-pressed sintering is used to densify the ceramic green body to obtain the shell-bionic ceramic tool.

Abstract: A hydrogel for cell-laden bioprinting, bioink, and a preparation method and an application thereof, relates to the technical field of biomedical polymer hydrogels. The hydrogel for cell-laden bioprinting is polymer gel formed by adding a cell-specific material into a matrix of alginate and gelatin and crosslinking and curing, wherein the cell-specific material is polypeptide selected according to different laden cells. The structures printed using the hydrogel may have the advantages such as adjustable mechanical properties, adjustable porosity, high biocompatibility, high printing accuracy, and high customizability, which may widely support the printing of human tissues and organs such as spinal cord, cartilage, and heart, and has good prospects for applications in tissue repair, organ transplantation and so on.

Abstract: An alumina-based ceramic tool material with low thermal expansion and a preparation process thereof, accordingly, the ceramic tool material may have both the high hardness of alumina ceramics after the hot pressing sintering, and reduces the thermal expansion coefficient of the overall ceramic material by adding the Sc2W3O12 as the negative thermal expansion phase, which improves the thermal shock resistance of ceramic tools in high-speed cutting engineering and meets the requirements of large temperature range during the machining of nickel-based superalloys. Moreover, the composite material does not use metal binder and has strong thermal stability even in the high-speed machining under extreme heat-force-chemistry coupling, so it has a high machining compatibility for nickel-based superalloys.

Abstract: A method and system of symbol measurement and combining (SMaC) provides near-optimal performance for each user independently by relying on rapid digital beamforming with near-ideal convergence properties. This approach is also provides near-ideal performance without any knowledge of user/jammer location and adapts instantly as those locations change. An iterative joint estimation method is used to determine a covariance matrix RXX, and a user beamsteering vector, ?.

Abstract: During an exchange of communications between a client and a server, the state of communications is monitored to determine if the client has lost communication with the server prior to completion of the exchange. If a loss of communication is detected, a recovery message is transmitted to the client, wherein the recovery message is received by the client after client communications with the network are re-established. The recovery message causes the client to send a response message to a predetermined network location. Receipt of the response message is an indication that the client has re-established communication. In such a case, the exchange is returned to a state that existed prior to the loss of communication.