Study of 3D Printing Model Aggregation and Retrieval Mechanism in Cloud Manufacturing With the rapid development of 3D printing technology and the continuous breakthrough of new material technologies, 3D printing has received more and more attention in the fields of industry, medical, sports, and education. In the cloud manufacturing environment, how to efficiently manage 3D printing models is a critical issue that needs to be solved urgently. The paper begins with a study of 3D printing model aggregation and retrieval mechanism based on this problem. Firstly, we devised a set of 3D printing model management framework with high scalability. Under this framework, a metamodel library and feature library are established to realize the aggregation of 3D printing models. Then, we developed a sketchbased 3D model retrieval method, which can help platform users to create and retrieve personalized 3D printing models easily. This study provides new ideas and a reference pattern for the model design and retrieval methods of existing commercial 3D printing platforms.

Consensusoriented cloud manufacturing based on blockchain technology: An exploratory study Abstract   In the era of cloud computing and Industry 4.0, significant research efforts on cloud manufacturing have been witnessed in recent years. Nevertheless, challenges, such as issues of trust, safety, payment, remain in this emerging area, which cause less confidence for industry to adopt cloud manufacturing. In this regard, the recent development of blockchain technology provides a potential viable solution thanks to its unique advantages in decentralization and security. As such, we propose a new framework of cloud manufacturing by integrating the blockchain technology. In essence, consensusoriented mechanisms are employed to generate the operating standards for the blockchain cloud manufacturing model. Moreover, based on the open source Ethereum code, we construct a simulation case study for 3D printing services using the proposed framework. A consortium or federated blockchain is simulated which uses ProofofAuthority (PoA) as the consensus algorithm of block generation. The simulation involves 939 job requests from 100 users, as well as 10 service providers. The knearest neighbors (KNN) algorithm is employed to recommend the service provider for each request. The results show that the providerxe2x80x99s score of service evaluation tends to be stabilize, and 934 requests for service are successfully fulfilled by the appropriate providers while the remaining 5 requests fail to be serviced.