Abstract: Obtaining effective transactions in the blockchain network initiated within a user-specified time window; generating a first transaction graph from the obtained effective transactions, wherein the first transaction graph is a directed graph, wherein each vertex of the first transaction graph represents a computing node in the blockchain participating in an effective transaction, and wherein each directed edge of the first transaction graph represents a transfer of data between two computing nodes; calculating a weight representing the intensity of data transfer between two computing nodes in an effective transaction; generating a second transaction graph that is a largest weakly connected component of the first transaction graph; assigning a zero rank score to computing nodes outside of the largest weakly connected component; calculating a rank score for each of the computing nodes in the second transaction graph based on the distribution of edge weights in the second transaction graph.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for ranking a plurality of blockchain computer protocols executing on a blockchain in a time period by ranking a plurality of computing nodes according to a metric in the time period; designating a number of the top-ranked computing nodes from the plurality of computing nodes as evaluating computing nodes; calculating a protocol score for each of the plurality of blockchain computer protocols, and ranking the plurality of the blockchain computer protocols based on the respective protocol scores.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for updating blockchain protocols. One of the methods includes maintaining, by a computing device, a blockchain according to a locally stored first protocol, wherein the blockchain comprises multiple blocks; receiving, by the computing device, a new block to the blockchain, wherein the new block includes information about a second protocol; verifying, by the computing device, that the information about the second protocol is from a trusted source; updating, by the computing device, the locally stored first protocol with the information about the second protocol; and processing, by the computing device, the request using the second protocol implemented using the information about the second protocol in the new block.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for implementing a consensus algorithm on a blockchain, including: ranking computing nodes according to a metric; designating a number of the top-ranked computing nodes as validator nodes; selecting a proposer node; causing the proposer node to create a proposed block; causing each validator node to participate in a first round of voting on the proposed block after depositing a first amount of digital currency; in response to at least two-thirds of the validator nodes voting approval: distributing to each approving validator node a second amount of digital currency; causing the validator nodes to participate in a second round of voting on the proposed block; in response to at least two-thirds of the validator nodes voted approval: distributing to each approving validator node a third amount of digital currency; and adding the proposed block to the blockchain.

Abstract: A boring bit for drilling is provided comprising one set of rotatable toothed wheels secured thereon as well as one set of tubular nozzles and one central nozzle for injecting drilling fluid from a chamber in bit body toward the bottom of a borehole. The boring bit comprises the inlet end of said tubular nozzle being secured on the bit body and connected with said chamber while its outlet end is quite close during operation to the lowest point of toothed wheels and the bottom of a borehole, and the fluid passage of said tubular nozzle from the inlet end to the outlet end is straight and cylindrical. Branch fluid passages are provided on the main fluid passage of said central nozzle for washing and cooling toothed wheels.