Earnings Management Practice in Bangladesh

This paper detects the existence of Earnings Management (EM) practice in Bangladesh. Total 105 manufacturing companies have been chosen from the different industrial sectors such as pharmaceuticals & chemicals, food & allied, cement, engineering, ceramics, tannery, textile & clothing, paper & printing, jute, fuel & power and miscellaneous. The well-known Beneish M score model has been used in detecting EM. The outcome shows that the percentage of non- manipulator companies is greater than manipulator companies except cement, paper & printing and jute industry. All out 39 % of manufacturing companies are likely manipulator where industry-wise pharmaceuticals & chemicals 28 % , food & allied 42%, cement 80%, engineering 42% , ceramics 0% , tannery 33% , textile & clothing 40 % , paper & printing 100%, jute 100% , fuel & power 25 % and miscellaneous 17% of manufacturing organizations are likely to be manipulator for 2017. This paper may help the stakeholder for distinguishing between likely and non-likely manipulator companies from the different industrial sectors, making a better decision and formulating policy to reduce the likelihood of manipulation. As Beneish Model is a probabilistic model, it is not unquestionably decisive from the identification that organizations are likely manipulators.

Study on hole machining for the constant feed rate of Al2O3 engineering ceramics through low-frequency axial vibration

Engineering ceramics are increasingly extensively applied in the aerospace, vehicle, armor protection and other fields due to their excellent performances such as high compression strength, high hardness, low density and high protection performance. However, engineering ceramics are typical difficult-to-machine materials, especially in the hole machining under constant feed rate, which limits the promotion and application. In this study, by combining a specially developed novel thin-wall diamond trepanning bit with a low-frequency axial vibration machining, the hole machining process for the constant feed rate of Al2O3 engineering ceramics was experimentally studied and the influence of the low-frequency axial vibration process on the axial drilling force, hole-wall surface roughness and edge chipping size of holes machined was analyzed. The results showed that the low-frequency axial vibration machining obtained a lower axial drilling force and a smaller edge chipping size compared to the traditional drilling process. Moreover, both the axial drilling force and the edge chipping size declined markedly with the rise in amplitude. However, the hole-wall surface roughness presented a rising trend due to the hammering effect of vibration. The process technology proposed in this article realizes the hole machining for a constant feed rate of Al2O3 engineering ceramics and provides a reference for the engineering lot-size hole machining of engineering ceramics.

Experimental Study on Machining Engineering Ceramics by Electrochemical Discharge Compound Grinding

Since engineering ceramics have many characteristics, including hardness, brittleness, and high melting point, traditional machining methods can no longer play a useful role in precision machining. Based on this situation, a platform of electrochemical discharge compound mechanical grinding was constructed and is presented in this paper, and machining experiments of micro-grooves were carried out in alumina ceramics. Grooves were observed by scanning electron microscope (SEM), and the morphology and the groove width of micro-grooves under different machining parameters were compared and analyzed. Furthermore, in order to study the improvement effect of mechanical grinding on machining quality, the surface roughness of micro-grooves was measured by a confocal material microscope. The results show that as the pulse power supply voltage increases or the frequency decreases, the width of the micro-grooves increases, and the morphology of the micro-grooves first improves and then deteriorates. With the increase of tool electrode rotation speed, the width of micro-grooves first increases and then remains unchanged, and the morphology and the surface roughness of micro-grooves first improves and then remains stable. Finally, the optimal parameters (power voltage of 20 V, pulse frequency of 400 Hz, electrode rotation speed of 600 rpm) were chosen to machine micro-grooves with good quality.