This paper empirically analyzes the price effects of annual earnings announcements from the perspective of investors' opinion divergence so as to provide not only empirical evidence to opinion divergence theoretical models but also a new way to the research of the price effects of information disclosure in A-share stock market. It is evidenced that investors' opinion divergence is negative correlated with the abnormal return around announcement dates,which indicates that investors' opinions converge at the disclosure of annual earnings announcements leading to overpriced stocks as a result of short sale constraints and opinion divergence to approach their fundamental values.It is also found that the price effects of converging opinions manifest themselves a few days before the formal announcement dates,which indicates that information leakage exists during disclosure processes of annual earnings announcements in A-share stock market.What's more,the negative correlations between investors' opinion divergence and price effects around announcements dates get more obvious with increasing institutional ownership and industrial concentration.
This paper is aimed at an effective control of the gob roof subsidence and safe recovery of coal occurring under the industrial squares. The control strategy follows from the use of thethree wastes( cemented filling material) to perform site filling experiments on area of +321 and coal layer goaf of N 4 at standing well of Babao. The paper provides an analysis of composition and performance of the three wastes( cemented filling material) and the factors affecting the strength of filling body,the reasonable arrangement of the filling process,and the following observation of the filling body. The results show that: the filling body made of the three wastes( cemented filling material) allows an active connection with the roof,thus ensuring an effective control of the roof in mined out area. The study may provide technical guarantee for the safe recovery of coal under the industrial square.
Aimed at an effective support of the gateway roof and control of the surrounding rock,this paper,based on the control mechanism of the gob-side entry retaining wall rock,introduces the application of the filling process and system designed for gob-side entry retaining with fly ash-high water filling materials and field test of roadside packing in gob-side entry retaining in the third working face in Xin'an coal mine,located in Shuangyashan. The results show that gob-side entry retaining is accompanied by an increase in roadway roof and floor due to the increasing distance of mining face; the filling bodies,capable of positive roof contact and an effective prevention of the deformation of the main roof,tend to be stronger due to increasing time; and filling strips of the better compactness are capable of preventing the harmful gas from escaping. The study serves as reference for the mine gob-side entry retaining in the mines of the similar conditions.
Since 2003,the new landscape flower plant area,sakura valley flower-enjoying area and Jiashanhong Forest Park have been built in Donggushan Forest Farm in Lujiang County to adjust the stand structure,speed up the low production forest improvement and plant landscape forests, giving full play to forest functions and bringing obvious ecological and social benefits. Forest tourism industry has also been developed which has been bringing economic benefits. The practice of Donggushan Forest Farm could be used for reference.
This paper introduces a viable response to the deformation of surrounding rock in 3832fully-mechanized face of Xin'an coal mine. This response approach hinges on the application of the controlling mechanism of surrounding rocks,the due consideration of the actual occurrence of working faces and the use of the fly ash-based cementing material as filling material to perform industrial test involving roadside packing for retaining entry along gob-side. The monitoring of gateway surrounding rocks and simulation of surrounding rock deformation using the FLAC3Dsoftware show that the presence of activation time of 0. 5 h and activator content of 0. 1% proportions allows the strength of test block to rise to 2. 42MPa after 24 h,indicating its ability to fulfill the support requirements of retaining entry; the agreement between the on-site measurements and the numerical simulations contributes not only to increasing the theoretical basis of the research,but also to improving filling material selection and filling system design for retaining entry along gob-side in the coal mines of similar conditions.
