The Adaptation of a Situational Judgement Test to Measure Leadership Knowledge in the Workplace

In recent times, situational judgment tests (SJTs) have emerged as an instrument of choice in organizations. This emergence is partly due to the high costs associated with developing and conducting high fidelity simulations such as assessment centers, coupled with the recent economic downturn affecting many organizations. The current study sought to validate an SJT as a low cost, alternate form of assessing leadership within an organizational context. A content validation study was carried out by retranslating items into eight dimensions and calibrating item responses. This study resulted in a content valid measure of leadership knowledge. Future studies should focus on further evaluating the psychometric properties of this new leadership assessment. Alternate forms reliability, convergent validity, and divergent validity studies, in particular, should be conducted to evaluate the new test

INVESTIGATION ON THE AIR-GAS CHARACTERISTICS OF AIR-HYDROGEN MIXER DESIGNED FOR DUAL FUEL – ENGINES

High smoke emissions, nitrogen oxide and particulate matter typically produced by diesel engines. Diminishing the exhausted emissions without doing any significant changes in their mechanical configuration is a challenging subject. Thus, adding hydrogen to the traditional fuel would be the best practical choice to ameliorate diesel engines performance and reduce emissions. The air hydrogen mixer is an essential part of converting the diesel engine to work under dual fuel mode (hydrogen-diesel) without any engine modification. In this study, the Air-hydrogen mixer is developed to get a homogenous mixture for hydrogen with air and a stoichiometric air-fuel ratio according to the speed of the engine. The mixer depends on the balance between the force exerted on the head surface of the valve and the opposite forces (the spring and friction forces) and its relation to decrease and increase the fuel inlet. Computational fluid dynamics (CFD) analysis software was utilised to study the hydrogen and airflow behaviour inside the mixer, established by 3.2 L engine. The Air-hydrogen mixer is examined with different speeds of engine1000, 2000, 3000 and 4000 RPM. Results showed air-hydrogen mixture was homogenous in the mixer. Furthermore, the stoichiometric air-fuel ratio was achieved according to the speed of the engine, the developed mixer of the AIR-Hydrogen mixing process provides high mixing homogeneity and engines with stoichiometric air-fuel ratios, which subsequently contributes to the high levels of efficiency in engine operation. In summary, the current study intends to reduce the emissions of gases and offer a wide range of new alternative fuels usage. While the performance of the diesel engine with the new air-hydrogen mixer needs to be tested practically

A numerical study to improve the position and angle of the producer gas injector inside the intake manifold to minimize emissions and efficiency enhancement of a bi engine

To develop a petrol engine so that it works under the bi-engine pattern (producer gas-petrol) without any additional engine modifications, a single-point injection method inside the intake manifold is a simple and inexpensive method. Still, it leads to poor mixing performance between the air and producer gas. This deficiency can cause unsatisfactory engine performance and high exhaust emissions. In order to improve the mixing inside the intake manifold, nine separate cases were modelled to evaluate the impact of the position and angle orientation inside the intake manifold on the uniformity and spread of the mixture under AFR=2.07. A petrol engine (1.6 L), the maximum engine speed (8000 rpm), and bi-engine mode (petrol-producer gas engine). The employ of the numerical simulation software (ANSYS workbench 19), the propagation, flow characteristics, and uniformity of the blend within the nine different cases were evaluated. According to the outcomes of the numerical simulation, it was found that creating vortices and turbulent flow for the producer gas and air inside the intake manifold is the perfect method to obtain a uniformity mixture of air and producer gas inside the intake manifold. In addition, extending the blending duration allows air and producer gas fuel to be mixed efficiently. Furthermore, the greatest uniformity and the maximum spread rate at the outlet of manifold are obtained in cases 1, 4, and 7, when the producer gas injector location is constant (P1, P2 or P3). In addition, the weakest spread of producer gas at the outlet of the manifold is observed in case 9 in comparison with the other cases. Moreover, it is observed that case (1) generated the maximum uniformity index (UI) leve

Impact of Lambda Value on Combustion Characteristics and Emissions of Syngas-Diesel Dual-Fuel Engine

A deep understanding of the ignition characteristics of syngas-diesel under different lambda values is essential for the application of dual-fuel combustion. In this study, the effect of increasing the lambda value was examined along with the emission characteristics and engine performance of syngas-diesel dual-fuel engines under a constant syngas-to-diesel substitution ratio of 52% at 2000 rpm engine speed. The work involved computational fluid dynamics analysis related to combustion for a four-stroke single-cylinder direct-injection engine. Combustion analysis was carried out using ANSYS Workbench (FLUENT) V16.1 software. According to the simulation results, the maximum pressure, temperature, and nitric oxide emission inside the combustion chamber increased with each increase in the value of lambda, while the emission of carbon dioxide and carbon monoxide decreased inside the engine

The use of assistive technologies among children with disabilities : the perception of parents of children with disabilities in Ghana

Purpose: Assistive technologies (ATs) are fundamental to the successful educational and societal inclusion of all children with disabilities. In particular, the use of ATs has been found to increase levels of independence in daily living and promote greater access to learning opportunities for children with disabilities. However, the knowledge base and baseline information on the use of ATs is limited in developing countries such as Ghana. In this study, we sought to explore the experiences of parents regarding the use of ATs by their children with disabilities in Ghana. Materials and methods: We used a survey questionnaire consisting of both open- and closed-ended questions to explore the perspectives of parents with children with disabilities (n = 35) who were attending the rehabilitation unit of a referral hospital. Results: Although participants acknowledged the benefits of ATs for the development and participation of their children in society, they noted barriers to the usage of ATs by their children. Among several barriers, parents mentioned that they lacked funds to purchase assistive devices. Some parents also mentioned the high cost of ATs and rehabilitation services. Conclusion: The need for government to include rehabilitation services and ATs in the National Health Insurance Scheme to ease the burden on participants and other implications of the findings for policymaking are extensively discussed. Implications for rehabilitation In an environment where there is negative attitude towards children and parents with disabilities, ATs are expected to encourage the participation and acceptance in society. Although many participants were aware of the benefits of ATs to their children, they reported barriers to usage among their children with disabilities. This study shows that poverty, limited health facilities, unfriendly environment and stigmatisation were barriers encountered by parents. We conclude that the government should expand health and rehabilitation facilities to encourage access and participation