Heart failure continues to be a major global health problem causing significant health issues and deaths. Left Ventricular Assist Device (LVAD) was developed as an alternative to heart transplant to support the patients with severe end stage heart failure. Despite the current advancement of LVAD, constant improvements are always being made in making it smaller LVADs tailored for patients with smaller physiology while still maintaining the flow ventricular pump capability to the body. This study evaluated the effect of using a smaller sized LVAD using Computation Fluid Dynamics (CFD) and compared with the initial pump size at their respective designed rotating speed. Two model variants were studied, the initial design with 44.8mm diameter impeller (2000 rpm rotating speed) and the smaller 37.0 mm diameter impeller (2500 rpm rotating speed). These designs were compared by their key criteria mechanical performances particularly the produced pressure difference along a range of flowrate and the efficiency curve. At the required flowrate of 5 L/min, the smaller sized 37.0 mm impeller was able to deliver the flowrate at a slightly higher pressure difference of 114.60 mmHg as compared to the 44.8 mm impeller at 106.01 mmHg. In overall, both model variant produced similar pressure-flowrate curve with the 37.0 mm impeller performing marginally better at higher flowrates. Efficiency was able to be maintained at 49-60 percent despite being a smaller impeller at a faster rotating speed. Miniaturizing the LVAD has been numerically demonstrated to be feasible to produce the needed flow output at the required pressure difference without affect efficiency significantly .

A safe and effective transportation system is a key factor for national development. To achieve sustainable development goals, technology needs to be used in transportation sector. The authors noticed that the country economy is affected by some factors such as the time wasted by passengers on long queue waiting for the bus to come. Also, the mass gathering contribute in a rapid spread of COVID-19 among passengers. In this study, an effective system for booking bus ticket and tracking bus location was developed. The system uses web- based application that allows the user to check the bus availability, its location and pay ticket on line. The system was developed using ESP8266 a WiFi based microcontroller to provide communication between bus officials and clients, GPS for tracking bus location, LCD for displaying the availability of passengers on a particular bus station, bus official application for receiving the client request and client application for service request and make a follow up. The study was achieved by presenting system circuit diagram and process flow chart. Also, implementation of a physical prototype linked with developed web applications was done. The system enables passenger to easily track the bus location in its real time position, to save time for manual reservation of bus ticket. The passenger crowd management system (PCMS) is secured and can be used by administrator (companies) of buses due to its efficiency in monitoring both buses and passengers.