Abstract: "Race against time" is the top priority of the R&D in emergency in the event of public health emergencies, and how to carry out timely and high-quality R&D is a common challenge for all mankind. After the outbreak of the COVID-19 epidemic in Jan. 2020, a large number of R&D organizations in China immediately engaged in the research, so that the epidemic had been initially controlled in 3 months by scientific intervention and social intervention in China, providing valuable empirical evidences for investigating the basic rules of R&D in emergency. In this study, 18 emergency R&D projects, which have made great contributions to fight against COVID-19, are taken as the research objects to explore the rapid-response mechanism of the R&D in emergency.
The multi-case study is applied as the research method. The case samples include 18 emergency R&D projects, of which 8 are related to the Scheme for Diagnosis and Treatment of 2019 Novel Coronavirus Pneumonia as "inside scheme case group", and of which 10 are not involved in the Scheme for Diagnosis and Treatment of 2019 Novel Coronavirus Pneumonia as "outside scheme case group". The sample selection criteria include response agility, R&D advance rate, and the achievements contributing to the epidemic prevention and control. The research process is as follows. Firstly, based on the grounded analysis, the data of multi-case samples have been processed to extract the factors related to the research questions, as well as the core categories and story lines. Secondly, the effects of various factors of each case sample have been evaluated, and a comparative analysis matrix of multi-case samples has been made. Finally, the cross-case analysis between two case groups and among all case samples have been carried out based on comparative logic from multiple perspectives, which further validates, revises and develops the construction established by grounded analysis, and forms a more explanatory theory for complex variables.
The result of grounded analysis shows that the core categories and story lines extracted from the "inside scheme case group" and "outside scheme case group" are consistent, releasing a relationship of mutual confirmation. The theory build up from these two case groups is mutually supported. The result of cross-case analysis shows that there are no significant differences between the two case groups in rapid-response performance, main forms, preconditions and types of participating organizations. The cross-case comparative analysis also shows that the greater effect of each factor, the stronger performance of the rapid-response. The cross-case analysis verifies the results of the grounded analysis of literal replication.
The research findings reveal that the scientific research facing to the unknown world is the main part of rapid-response activities in the R&D in emergency, and the main form, rules and preconditions comprehensively clarify the rapid-response mechanism of the R&D in emergency. The research based on re-discovery, the research based on re-application, and the research of Pasteur's Quadrant which takes into account both of the cognitive pursuit and application consideration, are the main forms of the rapid-response activities, and these three forms of researches support each other and grow iteratively in co-evolution. The scientific discovery chain and the exaptation rule have been followed, and the scientific research and social application has been quickly integrated to improve the rapid response to the public health emergencies. The instant sharing of resources and the rapid establishment of legitimacy provides preconditions to the rapid-response activities.
This study enriches the research of the technological innovation in emergency situation, develops a deeper understanding about the R&D in emergency management at the micro level, and provides the theoretical basis and managerial enlightenment for strengthening the scientific and technological support in emergency management, and optimizing the R&D system combining peacetime and wartime. The following suggestions are put forward to strengthen the rapid-response of the R&D in emergency. First, the main body and functions of the emergency R&D system should be made clear. Second, the basic scientific research must be enhanced with forward-looking deployment for the R&D in emergency. Third, the promotion mechanism for the rapid transformation of scientific research achievements ought to be improved in emergency situation. Fourth, the support of the biological data base, common technology platform, and relevant standards should be reinforced for the R&D in emergency. Fifth, the R&D resource allocation ought to be optimized in emergency situation.

Key words: R&, D in emergency, the rapid response, public health emergencies, COVID-19 epidemic