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The pulsed plasma thruster (PPT) is one sort of promising electric thrusters, but the low efficiency is always a big problem for PPT. Many researches have been working on solving this problem. However, there is still no significant breakthrough. This paper aimed to discuss some methods for improving the PPT's efficiency.

The causes for the low efficiency by analyzing the theoretical models of PPT are discussed, and the influences on PPT's performance investigated in terms of the structural or electrical parameters.

The change of structural or electrical parameters which influence the thrust efficiency significantly are taken into account. In the process of designing PPT, optimized structural and electrical parameters should be chosen to attain a better performance.

This analysis is mainly based on the parallel‐rail PPT.

The result of analysis is adopted, the higher thrust efficiency of PPT is expectable.

By introducing theoretical models and analyzing results of some researcher's experiments, this paper offers a method of designing PPT and attempts to help designer to choose appropriate structural and electrical parameters.

This chapter examines whether students’ perceptions of learning, attitudes, and performance are affected by the use of multimedia technology. Both traditional and multimedia methodologies were used in the financial accounting II course offered at one of the leading universities in Lebanon, using data collected from a sample of 110 students. In order to eliminate faculty-specific characteristics, the same professor taught all sections, thereby minimizing the effect different instructors might have had on student evaluations. Results indicate that students perceived the use of multimedia, specifically PowerPoint (PPT) lectures, as being more entertaining and organized than the traditional method; however, the latter methodology demonstrated more efficiency in terms of explaining theories, enhancing problem-solving abilities, and allowing for greater interaction. The two methodologies, however, did not demonstrate a significant statistical difference in terms of student learning and comprehension. Despite the positive student perception of PPT lectures, results suggest that the systematic approach of traditional methodologies exceeds PPT in emphasizing course materials and enhancing problem-solving abilities. As measured by their final grade, PPT methodologies affected student performance negatively, especially for below-average business students.

The purpose of this paper is to investigate the effect of power on pulsed plasma thruster (PPT) discharge current with respect to its peak, duration, and behavior while the power elevates in a low power range.

A rectangular parallel‐plate breech‐fed PPT has been developed with a self‐inductor coupling element connecting the PPT cathode to the ignitor plug cathode. The PPT has been operated in vacuum chamber at 10⁻⁶ mbar and its discharge current has been recorded using a Rogowski coil while input power has been changed by means of varying the capacitor voltage at given capacitance and frequency.

The analysis leads to elucidate the effects of input power on discharge current of a PPT employing a self‐inductor coupling element. The power varies within a range of less than 10 to more than 50 W. The results show that current peak rises from 5 to 10 kA while discharge duration and behavior seems to be independent of power within the operating range. Additionally, utilization of the coupling element seems to change the typical oscillating behavior of PPT discharge to a more efficient behavior.

The analysis is mainly focused on breech‐fed PPTs while employing a coupling element.

The paper analyzes the influence of power on discharge current of a PPT employing a self‐inductor coupling element. It clarifies the behavior of current peak, duration and behavior while power varies in a low power range. The effect of coupling element is shown to be promising. The results can be a help in design of μPPTs.

The purpose of this paper is to comprehensively review most of the significant works ever done worldwide to study the effects of essential parameters on pulsed plasma thruster (PPT) performance and to analyze the effects of each parameter on PPT performance.

All the important works studying PPT performance are categorized by the parameter they have studied and its effect on the thruster performance, and their works have been reviewed to analyze the influence of each parameter.

The analysis leads to elucidation of the effects of different geometrical parameters including aspect ratio, electrode width, electrode spacing, electrode shape, electrode length, and flare angle, in addition to the effects of other parameters such as electrode material, propellant type, propellant temperature, spark distance from propellant, pulse repetition frequency, discharge energy, capacitance, and hood angle on PPT performance.

The analysis is mainly focused on parallel‐rail breech‐fed PPTs and side‐fed PPTs and does not deal with co‐axial PPTs.

The paper reviews and analyses many of the considerable works ever done to contribute to clarify the effects of different parameters on PPT performance. The results of the current analysis can be of invaluable assistance in PPT design and optimization procedure and help the designer to develop a system with better performance characteristics.

Pervasive computing envisions seamless support for user tasks through cooperating devices that are present in an environment. Fluctuating availability of devices, induced by mobility and failures, requires mechanisms and algorithms that allow applications to adapt to their ever‐changing execution environments without user intervention. To ease the development of adaptive applications, Becker et al. (3) have proposed the peer‐based component system PCOM. This system provides fundamental mechanisms to support the automated composition of applications at runtime. In this article, we discuss the requirements on algorithms that enable automatic configuration of pervasive applications. Furthermore, we show how finding a configuration can be interpreted as Distributed Constraint Satisfaction Problem. Based on this, we present an algorithm that is capable of finding an application configuration in the presence of strictly limited resources. To show the feasibility of this algorithm, we present an evaluation based on simulations and real‐world measurements and we compare the results with a simple greedy approximation.

The purpose of this paper is to question the extent to which Sub-Saharan African cities are progressing towards promoting pro-poor economies through pro-poor tourism (PPT). It specifically examines how African cities are resilient towards attaining sustainable urban tourism destinations in light of high urbanization.

The methodological framework is interpretive in nature and qualitative in an operational form. It uses meta-synthesis to evaluate the causal relationships observed within Sub-Saharan African pro-poor economies to enhance PPT approaches, using Accra, Ghana, Johannesburg, South Africa, and Harare, Zimbabwe, as case studies.

Tourism development in Sub-Saharan Africa has been dominantly underpinned by neoliberal development strategies which threaten the sustainability of tourism in African cities.

The study is limited to three Sub-Saharan African countries. Further studies may need to be done in other developing countries.

It argues for good governance through sustainability institutionalization which strengthens the regulative mechanisms, processes and organizational culture. Inclusive tourism approaches that are resilient-centered have the potential to promote urban tourism in Sub-Saharan African cities. These findings contribute to the building of strong and inclusive Institutions for Sustainable Development in the Sub-Saharan African cities to alleviate poverty.

These findings contribute to the building of strong and inclusive institutions for sustainable development in the Sub-Saharan African cities to alleviate poverty.

The “poor” are always within the communities, and it takes a community to minimise the impact of poverty among the populace. The study is conducted at a pertinent time when most African government’s development policies are pro-poor driven. Though African cities provide opportunities of growth, they are regarded as centres of high inequality.

Knowledge sharing, as a kind of social behavior that incorporates collective intelligence to achieve a certain goal, has become a remarkable developing trend in recent years. Under the context of traditional teaching, this study aims to explore the manner in which students become effective in sharing knowledge to help optimize course design and improve our existing education.

Among 195 university students taking an elective, the effects of different incentives on group performance in completing tasks is explored on the basis of a randomized experiment.

Results show that intra-group cooperation can be helpful to student performance, whereas intra-group competition neither improves nor worsens student performance. The former is mainly driven by reciprocity, especially for that stimulated by inter-group competition, whereas the latter is stimulated by egoism. Thus, proper reciprocity can promote student behavior to increase voluntary contribution. In addition, intra-group differences do not interfere with group performance, especially task-oriented groups.

Certain suggestions are proposed to improve the curriculum design in large classrooms. Forming groups is the best way to strengthen student knowledge sharing. Within task-oriented groups, the incentives of inter-group competition can encourage students to deepen intra-group cooperation and thus effectively improve group performance under the conditions of external competition.

The purpose of this paper is to develop and characterize a pulsed plasma thruster (PPT) that does not need a spark plug to initiate the plasma discharge.

Two parallel rail thrusters were built and their performances were characterized inside a vacuum chamber to elucidate the effect of vacuum level and thruster geometry on the performance. The thruster electrical performance was quantified by measuring the voltage output from a Rogowski coil connected to the power supply. The thrust produced by the developed thruster was estimated by measuring the force exerted by the plume on a light weight pendulum, whose deflection was measured using a laser displacement sensor.

The thruster can operate without a spark plug. In general, the performance parameters such as thrust, mass ablation, impulse bit, and specific impulse per discharge, would increase with increasing pressure levels up to an optimum level due to the increase in discharge energy as well as the decrease in the total impedance of the plasma discharge. The discharge frequency is function of the breakdown potential, the total resistance in the equivalent circuit, and the capacitance of the circuit. The total impedance of the circuit decreases with pressure level and hence the discharge energy increases. The thrust efficiency is found to be affected by the thruster geometry as well as the discharge energy.

The studies reported in this paper have been carried out at relatively higher pressure levels compared than prevail in space. However, it should be possible to extrapolate these results to the lower vacuum levels at which the performance is independent of the geometry.

The results reported in this paper suggest a design guideline for auto‐initiated PPT.

If the spark plug is eliminated, the size of the thrusters can be reduced and arrays of such thrusters can be manufactured using micro electro mechanical systems techniques, which can provide tremendous control authority over the satellite positioning.

This study aims to apply the appreciative inquiry approach (AI) to develop a tourism strategy for poverty alleviation in marginalised communities. The focus is to provide practical insights for leveraging tourism to drive positive socio-economic change for the impoverished, using Rosetta, a port city in Egypt with cultural and historical significance, as a case study.

This qualitative applied study uses the four-D phases of AI and thematic analysis to strategise tourism development in Rosetta. Through interviews, focus groups and field visits, the study identifies tourism potential, stakeholder aspirations and actionable strategies for sustainable development. The approach prioritises a bottom-up, community-centric and stakeholder-involved process, aiming for inclusive and equitable growth.

The study revealed Rosetta’s underutilised tourism potential, emphasising heritage tourism. Although tourism offers some economic benefits, its impact on alleviating poverty in Rosetta remains limited. A holistic strategy for tourism development in Rosetta is proposed for economic growth and poverty reduction, focusing on sustainable management, local empowerment, enhanced marketing, improved infrastructure and diversified tourism offerings.

While AI is not new in qualitative studies, the novelty of this study lies in its application to tourism planning for poverty alleviation in a marginalised community like Rosetta, introducing a comprehensive tourism strategy with an original framework applicable to comparable destinations. The study’s significance is emphasised by providing actionable strategies for policymakers, valuable insights for practitioners and enriching the discourse and methodology on pro-poor tourism for academics, representing a step towards filling the gap between theoretical concepts and practical strategies.

Tourism is one of South Africa’s fastest growing sectors. Pro-Poor Tourism (PPT) is an approach to tourism development that results in increased net benefits for poor people. It enhances the linkages between tourism businesses and poor people, so that tourism’s contribution to poverty reduction is increased. The South African Township Tourism Organisation tries to implement PPT by providing tourists with the chance to learn about the country and its history in an authentic way. The authors took a sample of Tour Operators registered with Tourism South Africa in Cape Town, Johannesburg and Pretoria that include the two biggest townships Khayelitsha and Soweto. They used in-depth interviews to identify the kind of tours offered and the extent to which local communities are involved in and benefit from these tours. Results show that in terms of direct poverty alleviation township tourism is considered to be only moderately successful. The tour operators emphasised the need for more social investment and for local government to play an active role in encouraging the employment of more local people.