Blast furnace operation is a complex phenomenon; maximising productivity requires a balance of burden characteristics. Meeting the targets of optimum sinter strength and minimum slag volume is a matter of concern for high alumina (2 . 0-2 . 1%) iron ore fines. To achieve reduced slag volume MgO in the sinter may be reduced and sinter strength maintained by addition of coke breeze. However, the associated increase in fuel rate during sintering raises the FeO content. The effects of increasing FeO and lowering MgO on the softening melting behaviour of burden materials have been assessed in laboratory experiments and the results compared with data from blast furnace operations at Tata Steel. It was found that with sinter containing .12%FeO, erratic furnace behaviour was encountered and energy adjustment was required with the reduction in MgO (1 . 77-1 . 48%) to ensure smooth operation.

This article summarizes the outcome of research work carried out to improve the performance of the oxygen lance in the LD steelmaking process. It is stated that the lack of control of the foamy slag and the augmentation of interfacial area creation between the slag and metal are the major hindrances in running the process effectively for improved turn-down steel quality. The ineffectiveness of the existing design in producing liquid metal droplets in the presence of slag foam is explained. In order to augment the droplet generation, a new oxygen lance with a central subsonic nozzle through which flow can be controlled has been introduced and its blowing performances studied using numerical and water model studies. The jet characteristics studied in the numerical simulations show no jet coalescence. The interferences of the jets with the bath have further been analyzed by hydrodynamic model studies. It has been found that the droplet generation rate improves significantly due to the presence of the central jet. Further, it has been observed that controlling the flow rate through the central hole can be used as an effective process control tool.

Traffic accidents involving pedestrians have become a major safety problem in most of the developing countries like India due to rapid urbanization, increase in vehicular growth and lack of adherence to traffic regulations by both drivers and pedestrians. The existing roads design does not provide adequate facilities for pedestrians and hence, there exists a constant conflict between the pedestrians and the vehicles in sharing the limited space available on a road. At intersections, pedestrian crossing behavior is even more complex since the vehicles have very little response time to control the vehicles, particularly in urban areas. All these issues are pointing towards the research work required for studying the road crossing behavior of pedestrians at urban intersections. The main motivation of this study is to investigate the changes in pedestrian road crossing behavior of an intersection under mixed traffic conditions before and after signal installation. For this purpose, traffic and pedestrian data were collected from an intersection located in Mangalore city. Different parameters like age, gender, crossing patterns, crossing times, waiting times and crossing speeds of pedestrians, speed and types of vehicles and vehicular flows were extracted from the videos. The study analysis shows that majority of the pedestrians chooses one-step crossing after signal installation since they get sufficient gap to cross the road during the red phase of the signal provided for vehicles. The waiting times of the pedestrians were increased after installation of the signal since pedestrians have to wait for gaps until the vehicles get dissipated during the green phase. The 15th percentile crossing speed of pedestrians for both the scenarios were lesser than the crossing speed (1.2 m/s) used in pedestrian facility design as per Indian Road Congress (IRC 103). Critical gap of pedestrians has reduced marginally due to the decrease in crossing speeds of pedestrians after installation of the signal. A model was developed considering pedestrian gap size as the dependent variable and pedestrian and traffic characteristics as the independent variables using multiple linear regression (MLR) technique. A total of 468 and 333 accepted gaps of pedestrians were used for modeling the before and after scenarios, respectively. It was found that pedestrian jaywalking behavior is reduced after installation of the signal. The study concludes that after signal installation the factors such as traffic volume, average speed of vehicles and age-group play a predominant role in estimating the pedestrian gap acceptance. This study will be useful for understanding the complex pedestrian road crossing behavior at intersections under mixed traffic conditions. The findings of this paper have great implications for designing pedestrian facilities and also, for devising traffic management measures for pedestrian safety.

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