Distributed metadata service system of certification resource sharing of pollution-free agricultural products

In order to utilize and share the digital certification resources for pollution-free agricultural products, the research of the key technology for the metadata service of the certification resources was conducted in this paper, taking the wide-area scattered storage pollution-free agricultural products digital resources as the investigated subject and transparent access to the certification resources. Through the feature analysis of completeness and relevance of the certification resources, the multi-level model of the certification resource set was proposed to conduct the organization and division of the resources. On the basis of the certification resources organization and the relations revelation between the resources, the metadata standards were designed and the certification resources metadata frame model was presented in this paper. Based on resource allocation and management and service support, the hierarchy of the certification resources and the functional structure of the sharing service was levelly sliced and distributed in the sharing service network composed of the center domain and resource domain to construct the certification resources sharing service system structure. Moreover, the core technologies such as the metadata distributed storage, metadata request and so on also were discussed in this paper. Finally, a virtual certification resources database integrated by the wide-area scattered certification resources through the certification resources sharing service was established to provide the unified resources logical view to the service objects such as consumers, enterprises, functional technology departments, governments and achieved the transparent resources access. This research also provides the technical support for the transition of the certification work from the evaluation of conformity to the market supervision of the agricultural products quality safety and has good prospects of application and promotion.