Influence of Day-length Enhancement through Night-breaking by Artificial Lighting on Off-season Dragon Fruit Production

The effect of artificial lighting in order to enhance day length for off-season dragon fruit production was examined for the first time in Bangladesh. A two factorial experiment was conducted at dragon fruit orchard of Agricultural Research Station, Pahartali, Khulshi, Chattogram to find out the best lighting duration and bulb for off-season dragon fruit production. Two factors were bulb and lighting duration for this experiment. The performance 6 hours lighting duration was significantly superior than other treatments in case of bud/pillar (43.80), fruit/pillar (43.80), fruit length (9.31 cm), fruit breadth (8.5 cm), individual fruit weight (344.62 g), yield (16.58 t/ha). 100 W IB having light intensity 225.96 lux showed superior performance over other treatments in case of bud/ pillar (49.44), fruit/pillar (34.56), fruit length (9.54), fruit weight (336.99 g), TSS (9.28%), yield (18.13 t/ha). The treatment combination (100 W IB for 6 hrs lighting) produced the highest number of fruit/ pillar (36.33), bud/pillar (54.00), fruit length (9.66 cm), fruit breadth (8.99 cm), yield/ pillar (12.41 kg) and yield (19.85 t/ha).In control dragon fruit was unable to produce flowering due to short day length. So artificial lighting of 6 hrs with 100 W IB from 18 pm to 24 am was superior method for off-season dragon fruit production.

Strain energy analysis of floor heave in longwall gateroads

Floor heave in longwall gateroads is a severe issue that affects mining safety and efficiency. Researchers, however, have limited understanding on the floor heave mechanism because the deformation of post-failure rocks in the floor was seldom considered previously. In this study, we developed a theoretical model using the strain energy theory to investigate the post-failure deformation of rocks. This model was validated before being implemented into a numerical modelling package, FLAC 3D , for floor heave analysis. Based on a case study of a longwall entry employing a stiff–yield pillar configuration, we observe that massive floor heave occurs at the entry rib that takes less loads (yield pillar) and eventually propagates towards the other rib bearing a significant amount of loads (stiff pillar). This observation sheds light on the floor heave mechanism in longwall gateroads and has major implications for coal mine ground control.