For any scheme M with a perfect obstruction theory,Jiang and Thomas associated a scheme N with a symmetric perfect obstruction theory.The scheme N is a cone over M given by the dual of the obstruction sheaf of M,and c...For any scheme M with a perfect obstruction theory,Jiang and Thomas associated a scheme N with a symmetric perfect obstruction theory.The scheme N is a cone over M given by the dual of the obstruction sheaf of M,and contains M as its zero section.Locally,N is the critical locus of a regular function.In this note we prove that N is a d-critical scheme in the sense of Joyce.There exists a global motive for N locally given by the motive of the vanishing cycle of the local regular function.We prove a motivic localization formula under the good and circle compact C*-action for N.When taking the Euler characteristic,the weighted Euler characteristic of N weighted by the Behrend function is the signed Euler characteristic of M by motivic method.As applications,using the main theorem we study the motivic generating series of the motivic Vafa-Witten invariants for K3 surfaces.展开更多
This paper analyzes sixty-five influential collective turnover events that occurred from year 2000 to 2011. The first finding is that collective turnover is most likely to take place at the departmental level because ...This paper analyzes sixty-five influential collective turnover events that occurred from year 2000 to 2011. The first finding is that collective turnover is most likely to take place at the departmental level because staff in the same department tend to reach collective consensus more easily. The second finding is that collective turnover takes place more frequently in industries such as IT, retailing and banking. The third finding is that collective turnover often begins with the turnover of managers at the departmental or higher levels. With further exploration of collective turnover, we notice that the institutional environment during China＇s economic transition is the external constraint on collective turnover, and improper management policies is the internal driving factor. We also find that motivations vary for employees at different levels in the organization. Finally, we conclude that organizational outcomes of collective turnover are not only linked with the absolute level of turnover, but ＂quality＂ factors of collective turnover such as relative turnover ratio, occurrence frequency, employee type, rank and work experience should also be taken into consideration.展开更多
文摘For any scheme M with a perfect obstruction theory,Jiang and Thomas associated a scheme N with a symmetric perfect obstruction theory.The scheme N is a cone over M given by the dual of the obstruction sheaf of M,and contains M as its zero section.Locally,N is the critical locus of a regular function.In this note we prove that N is a d-critical scheme in the sense of Joyce.There exists a global motive for N locally given by the motive of the vanishing cycle of the local regular function.We prove a motivic localization formula under the good and circle compact C*-action for N.When taking the Euler characteristic,the weighted Euler characteristic of N weighted by the Behrend function is the signed Euler characteristic of M by motivic method.As applications,using the main theorem we study the motivic generating series of the motivic Vafa-Witten invariants for K3 surfaces.
文摘This paper analyzes sixty-five influential collective turnover events that occurred from year 2000 to 2011. The first finding is that collective turnover is most likely to take place at the departmental level because staff in the same department tend to reach collective consensus more easily. The second finding is that collective turnover takes place more frequently in industries such as IT, retailing and banking. The third finding is that collective turnover often begins with the turnover of managers at the departmental or higher levels. With further exploration of collective turnover, we notice that the institutional environment during China＇s economic transition is the external constraint on collective turnover, and improper management policies is the internal driving factor. We also find that motivations vary for employees at different levels in the organization. Finally, we conclude that organizational outcomes of collective turnover are not only linked with the absolute level of turnover, but ＂quality＂ factors of collective turnover such as relative turnover ratio, occurrence frequency, employee type, rank and work experience should also be taken into consideration.
