Zareena Kausar

Bio: Zareena Kausar is an academic researcher from Air University (Islamabad). The author has contributed to research in topics: Mobile robot & Machining. The author has an hindex of 5, co-authored 35 publications receiving 109 citations. Previous affiliations of Zareena Kausar include University of Auckland & Air University (United States Air Force).

Potential of waste cooking oil biodiesel as renewable fuel in combustion engines: A review

Abstract: As non-renewable conventional fossil fuel sources are depleting day by day, researchers are continually finding new ways of producing and utilizing alternative, renewable, and reliable fuels. Due to conventional technologies, the environment has been degraded seriously, which profoundly impacts life on earth. To reduce the emissions caused by running the compression ignition engines, waste cooking oil (WCO) biodiesel is one of the best alternative fuels locally available in all parts of the world. Different study results are reviewed with a clear focus on combustion, performance, and emission characteristics, and the impact on engine durability. Moreover, the environmental and economic impacts are also reviewed in this study. When determining the combustion characteristics of WCO biodiesel, the cylinder peak pressure value increases and the heat release rate and ignition delay period decreases. In performance characteristics, brake-specific fuel consumption increases while brake-specific energy consumption, brake power, and torque decrease. WCO biodiesel cuts down the emissions value by 85% due to decreased hydrocarbon, SO2, CO, and smoke emissions in the exhaust that will effectively save the environment. However, CO2 and NOx generally increase when compared to diesel. The overall economic impact of production on the utilization of this resource is also elaborated. The results show that the use of WCO biodiesel is technically, economically, environmentally, and tribologically appropriate for any diesel engine.

The Effect of Terrain Inclination on Performance and the Stability Region of Two-Wheeled Mobile Robots

Abstract: Two-wheeled mobile robots (TWMRs) have a capability of avoiding the tip-over problem on inclined terrain by adjusting the centre of mass position of the robot body. The effects of terrain inclinati...

Performance enhancement of a statically unstable Two Wheeled Mobile Robot traversing on an uneven surface

Abstract: A Two Wheeled Mobile Robot (TWMR) is a highly nonlinear and open-loop unstable system. Dynamic analysis and control design to keep the body of the robot balanced has been an area of research in the last decade. This problem has been dealt by many researchers for the robot motion on flat surfaces. A few studies have addressed the motion control on constant sloped path. This work studies the control of TWMRs on an uneven surface. With respect to previous results in the literature, the main contributions of this study are the dynamical modeling and control design of a two-wheeled mobile robot while traversing on uneven surface, in particular a single bump. A criterion has been proposed for the system performance evaluation. The system response to a baseline control and proposed Gain Scheduling control is quantified in simulation through proposed criteria. The results show an improvement in system performance on an uneven surface.

Mobile robot path planning for circular shaped obstacles using simulated annealing

Abstract: Many heuristic methods are used for path planning by researchers in the past and contemporary work but due to easy implementation, convergence properties, capability of escaping local optima and the use of hill-climbing moves have made simulated annealing (SA) a good choice for path planning. In this research the simulated annealing algorithm is used to obtain a collision-free optimal path among fixed circular shaped obstacles for a mobile robot. A feasible path is computed by series of points in cells generated between start to goal point. The effectiveness of the proposed algorithm in different environments is shown through simulation results.

Numerical Simulation of a Novel Dual Layered Phase Change Material Brick Wall for Human Comfort in Hot and Cold Climatic Conditions

Abstract: Phase change materials (PCMs) have a large number of applications for thermal energy storage (TES) and temperature reduction in buildings due to their thermal characteristics and latent heat storage capabilities. The thermal mass of typical brick walls can be substantially increased using a suitable PCM primarily based on phase change temperature and heat of fusion for different weather conditions in summer and winter. This study proposed a novel dual-layer PCM configuration for brick walls to maintain human comfort for hot and cold climatic conditions in Islamabad, Pakistan. Numerical simulations were performed using Ansys Fluent for dual PCMs layered within a brick wall for June and January with melting temperatures of 29 °C and 13 °C. This study examined and discussed the charging and discharging cycles of PCMs over an extended period (one month) to establish whether the efficacy of PCMs is hindered due to difficulties in discharging. The results show that the combined use of both PCMs stated above provides better human comfort with reduced energy requirements in Islamabad throughout the year than using a single PCM (29 °C) for summer or winter (13 °C) alone.

Heating and cooling energy trends and drivers in buildings

Abstract: The purpose of this paper is to provide a source of information on thermal energy use in buildings, its drivers, and their past, present and future trends on a global and regional basis. Energy use in buildings forms a large part of global and regional energy demand. The importance of heating and cooling in total building energy use is very diverse with this share varying between 18% and 73%. Biomass is still far the dominant fuel when a global picture is considered; the role of electricity is substantially growing, and the direct use of coal is disappearing from this sector, largely replaced by electricity and natural gas in the most developed regions. This paper identifies the different drivers of heating and cooling energy demand, and decomposes this energy demand into key drivers based on a Kaya identity approach: number of households, persons per household, floor space per capita and specific energy consumption for residential heating and cooling; and GDP, floor space per GDP, and specific energy consumption for commercial buildings. This paper also reviews the trends in the development of these drivers for the present, future – and for which data were available, for the past – in 11 world regions as well as globally. Results show that in a business-as-usual scenario, total residential heating and cooling energy use is expected to more or less stagnate, or slightly decrease, in the developed parts of the world. In contrast, commercial heating and cooling energy use will grow in each world region. Finally, the results show that per capita total final residential building energy use has been stagnating in the vast majority of world regions for the past three decades, despite the very significant increases in energy service levels in each of these regions.

Process optimization of ultrasonic-assisted biodiesel production from waste cooking oil using waste chicken eggshell-derived CaO as a green heterogeneous catalyst

Abstract: In this study, waste chicken eggshell-derived CaO particles were synthesized as heterogeneous catalyst, and their structural and morphological properties were evaluated. CaO was used as a catalyst in ultrasonic-assisted biodiesel production from waste cooking oil (WCO). Response surface methodology (RSM) based on central composite design (CCD) was applied to investigate and optimize the influence of reaction parameters, such as catalyst loading (6–12 w/w%), methanol to oil ratio (6:1–12:1 m/m), ultrasonic power (150–300 W), and reaction time (20–40 min), on biodiesel yield and specific energy consumption (SEC). The results showed significant effects of the parameters on the biodiesel yield and SEC, except for the effects of molar ratio on SEC. Moreover, the optimal reaction conditions were a catalyst loading of 6.04 w/w%, methanol to oil molar ratio of 8.33 m/m, ultrasonic power of 299.66 W, and reaction time of 39.84 min, leading to a biodiesel yield of 98.62% and SEC of 5.01 kJ.g −1 . • Transesterification of WCO was carried out over waste chicken eggshell-derived CaO. • The catalysts were characterized by various analyzes such as STA, XRD, FE-SEM and, EDS. • CCD- RSM was applied to optimize biodiesel yield and SFC in ultrasonic-assisted biodiesel reaction. • The optimum condition was 6.04 w/w% CaO, M:O 8.33 m/m, 299.66 W and 39.84 min. • A biodiesel yield of 98.62% and SFC of 5.01 kJ/g were obtained based on the optimum condition.

Path Planning of UAV Based on Improved Adaptive Grey Wolf Optimization Algorithm

Abstract: Aiming at the three-dimensional path planning of unmanned aerial vehicle (UAV) in the complex environment of material delivery in earthquake-stricken areas, this paper proposes an improved adaptive grey wolf optimization algorithm (AGWO) based on the grey wolf optimization algorithm (GWO). There are two main contributions of the proposed method. Firstly, we propose an adaptive convergence factor adjustment strategy and an adaptive weight factor to update the individual’s position. The effectiveness of the improved algorithm is verified by the convergence analysis and the test function simulation experiment. Secondly, the improved algorithm is applied to UAV path planning, the environmental map model is established by integrating digital elevation map and equivalent mountain threat model, and the performance evaluation function is established by fitting the calculated track length. The simulation results show that the improved AGWO is superior to the traditional intelligent algorithm in convergence precision, speed and stability performance, and it is effective for 3D trajectory optimization in complex environment.