Research on Construction of Cloud Service Platform of Sci-tech Information for Agricultural Research System

. In this paper, an overall architecture and service model of cloud service platform of sci-tech information based on cloud computing for agricultural research system were proposed, aiming at promoting the co-construction and sharing among information service institutions in agricultural research system. The platform will integrate resources and services of co-construction institutions into a shared body, and form a new science and technology information service system to provide network infrastructure, resources, platform and various application services for agricultural research system. And through dynamic management and distribution of a variety of services, it will meet the needs of users at different levels, such as institutions, academic teams and individuals and so on.


Introduction
Cloud computing is a new calculation model developed on the basis of distributed computing, parallel processing and grid computing and so on. Its core is to provide mass data storage and network computing services. Based on cloud computing, cloud service is a new IT service delivery model, aiming to combining technology and business delivery for the users [1]. Cloud is the center of the data storage and application service.
The emerging of cloud computing services has attracted more attention from various areas in the world. Google, IBM, Amazon, Microsoft and other IT giants have launched their own cloud initiative [1]. In the field of library and information, OCLC (Online Computer Library Center) launched the first cloud-based collaborative Web-level library management services [3] [4]. In China, CALIS (China Academy Library and Information System) has carried out the development strategy of CALIS cloud computing at the earlier time, as well as research and exploration of cloud service platform of digital library [5].
Regarding scientific research information service system (library) as research object, this paper focused on the application of cloud computing in resources construction and services of agricultural research system. With the rapid development of internet and other modern information technology, and the increased pressure of agricultural science and technology self-dependent innovation in China, the requirements of information and services of agricultural research system are undergoing significant changes. Firstly, with the rapid development of the internet and a number of commercial information institutions, more pathways are provided to access information for researchers. The needs of researchers for information services provided by Library have gradually been weaken.

Significance of Construction
Secondly, the demand for science and technology information of scientific research personnel is more urgent. In particular, they need to keep abreast of the latest research developments of disciplines and peers progress both at home and abroad. The needs of information content are also charactered by timeliness, specialty, comprehensiveness, dynamics and knowledge. The third change is that the way of access to information is featured with digitization, networking, and mobility. The network of scientific communication and collaboration environment become the mainstream of modern scientific research. The forth one is that researchers need more information finding ways and various information processing tools. They pay more attention to the preservation, sharing and utilization of the academic achievements.
Due to these changes, the library and other specialized information service organization have faced serious challenges. Because of lack of funding, manpower, knowledge, basic conditions and others, single information agency increasingly highlights limitations in conducting resource construction and providing services.
Obviously, there need union, co-building, sharing and co-prosperity. What comes first is infrastructure construction. The infrastructure is weak in some Libraries of the academy system or information agency, and the capacity to update and maintain is inadequate. These affect the quality of the information service. But there are also some individual information services which have obvious advantages of the resources, technology, personnel, and equipment as well. The second issue is resource sharing.
Although the academies of agricultural research system like CAAS have accumulated a certain amount of information resources for a long time via various channels, including the purchased electronic resources and self-built specialized databases, which played an important role in the service, it is still unable to meet the expanding needs of scientific users. And for a long time, the resource construction and service capacity are quite different and collaborative sharing is weaker among the various information institutions of agricultural research system. These lead to coexist of repeated construction and inadequate resources. That not only is very wasteful, but also affects the overall effect of service. Thirdly, there are also a lot of same subjects, although the academies of agricultural research system have their own unique fields of study. It is more prominent for the role of joint construction of information resources and providing service for researchers with similar research direction, although they are distributed in different research institutions.
Cloud computing technology provides an effective means to solve these problems. It opened up a new train of thought (library) of the co-construction and sharing for promoting information service organization (library) of agricultural research system in China. In this context, based on cloud computing, we proposed the construction of cloud service platform of agricultural scientific research system. Its significances lie in as follows: (1)To promote the development of resource construction and service alliance of agricultural research system in China, to co-build a new system for agricultural research service system, achieve value adding and extension under limited conditions of resources, systems, services, technology etc.. It can provide broader and more convenient service for scientific users, and reduce a lot of problems such as scattered resources, self-limited service system, disorders of multi-service gateway when accessing system, and so on.
(2)To reduce duplication of construction through integration of high-quality resources of agricultural research system, and alleviating resources construction and service limitations of the individual information service institution especially due to lack of technology, talent, capital, ,to improve overall resources support ability and service level of agricultural research system.
(3)To adapt with the changing environment. With the popularization of internet services, it is supposed to take the advantages of professional information services, focusing on the construction of characteristic resources of agricultural subject, which are scarce on the Internet, expanding specialized knowledge services. And the private cloud or hybrid cloud service platform of sci-tech information for agricultural research system can be built when enjoying the services of internet public cloud, to improve competitiveness of agricultural specialized information service organization.

Construction Infrastructure
The construction of the proposed platform not only needs infrastructures such as good network environment, High-Performance Server, storage equipment, but also calls for rich agricultural professional data resources and service applications along with co-construction and sharing mechanism and strong desire in the system. As a result, we should fully consider the existing resources and conduct the optimized integration and promotion.

Platform Overall Architecture
The proposed platform is a digital research information platform based on a variety of technologies and services, which provides diversified services for service institutions, Cloud service center has a long-term, basic, stable resource and service support from NAIS, Agridata, NSTL, other agricultural research institutes, the Internet open access system, and third-party system. Among them, NAIS mainly focuses on literature construction and service, while Agridata aims at integration and sharing of scientific data. By integrating and reorganizing these sources, as well as encapsulating and clouding the core function modules of these service system, cloud service center builds a series of cloud service components with both versatility and reusability, including resources, tools, systems, Open APIs, and Web Services. It provides services for cloud users, such as professional information service agencies, research institutions, academic teams, individual users and third-party users, etc. As the resource and service center of agricultural research system, cloud service center can harvest resources shared by various users, thus forming a shared knowledge base of national agricultural research. Meanwhile, it is responsible for global resource storage, organization, management, distribution and scheduling, conducting service monitoring and service statistics, maintaining login accounts and user rights, deploying various kinds of application service, and securing the safety of resource and service, etc. A resource sharing and collaborative service model can be formed through cloud service center, a public service portal of information institution and a personalized knowledge service platform for organizations, groups, individuals, disciplines and projects, which will enhance the overall service ability of agricultural research system. c Institutional users, Teams , Individual users ... ..

Personalized services portal for users
Public service portal of information agencies

Resources construction and services
Cloud service center

Cloud Service Model
The platform is composed of a series of services, which can be divided into 5 layers as shown in the Fig.2. The 5 layers are infrastructure layer, platform service layer, application service layer, cloud service layer and cloud clients, respectively [8][9][10][11][12].  can not only make full use of superior server resources, cyber source and storage resources within the system, but also decrease the idle resources, avoiding repeated purchase of hardware resources, and reducing the burden of weak institutions in the construction of hardware resources.

Platform service layer (PaaS)
The platform service layer (PaaS) is a collection of software resources with generality and reusability, mainly including the basic and core services such as resource acquisition, processing, storage, organization, management, publishing, searching, sharing and use, which can provide direct service for users at all levels, and also services through Open API. The PaaS service provides services to support the professional information service organization and users to create local personalized service system of their own, which to a certain extent solved the problem of lacking technology in network information service of the institutions.

Application service layer
The application service layer (SaaS) is to provide the end user with interface and application services. It mainly includes: resource retrieval, cataloging, document delivery, reference, SDI service, sci-tech trend monitoring, institutional repository, sci-tech novelty retrieval, intelligence service and the deep-seated personalized knowledge services aimed at scientific research institutions, academic team and individual users, such as knowledge management, knowledge map, knowledge navigation, and knowledge association.

Cloud service layer
The Cloud service layer is a service interface for users at all levels, mainly through the professional information service portal (including public service portal of information agencies and personalized service portal for scientific research institutions, academic teams and individuals). The gateway construction can use the IaaS, PaaS, SaaS and other services that the platform provides, including various forms of data, tools, equipment, and systems. However, the permissions different users have when accessing the resource and services are different.

Cloud clients
The cloud clients are the main terminals with which users have access to the service portal and use the resources and services.

Service Mode
This platform can offer flexible, dynamic service configuration and service delivery according to users' needs. Considering permission to access, intellectual property and services and other factors, the Cloud service platform provides different services such as paid services, free services, and adjustment access by scenario sensitive.
The information service institutions of agricultural research system provide following services: ① The platform tools are provided which support the information service institutions to establish local personalized service portal. Those institutions will no longer need to build and develop their own information software. They only need access the needed services according to their business demands in accordance with the contract. This is the way to implement co-construction and sharing between application service systems and information services.

Conclusion
Undoubtedly, Cloud Computing brings unprecedented challenges and chances to the information service industry. The cloud service platform of agricultural research system presented in this paper will promote the resources construction and the development of sharing services union among information service institutions, and improve the overall information service of agricultural research system. However, there are still some problems to be solved. They include the issues of cloud computing security, resources copyright and ideas identification, how to reach an agreement about coalition building between agricultural research systems, and how to establish an efficient and mutually beneficial pattern effectively integrating the technologies, resources, services of member institutions. In short, in the global open information environment, the alliance of professional information institutions not only contribute to their development, but also facilitate more progress of agricultural sci-tech information service industry, with the continuous competition of the business information agencies, publishers, and under the condition of limited resources,.
Moreover, it is beneficial to the broad masses of agricultural science and technology innovation and industrial development.