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This article deals with some of the stability, control and handling problems that have arisen as a result of drastic changes in aircraft configuration coupled with the advent of supersonic flight at high altitude. The article will be published in two parts. The present part contains a brief introduction to the subject of aircraft stability and control in addition to a description of the longitudinal characteristics of supersonic aircraft. The second part will be published in our next issue, and will deal with the lateral characteristics of supersonic aircraft. Some of the problems encountered in the design of the flying control system for this type of aircraft and an indication of the methods and techniques used for solving the various stability problems are also presented in the second part.

APPLICATION of the so‐called high energy liquid fuels and high energy liquid oxidizers to power plants based on the jet propulsion principle is receiving the increasing interest and attention of rocket propellant chemists and power plant engineers universally. The aspect of substantially increased—as much as 50 per cent— energy per pound of propellant load or per cubic foot of propellant tankage over today's propellants has whetted scientific appetites and justified probing the field of high energy chemicals to determine, as logically and as practically as we can at the present time, the gains, problems, limitations and applications of these higher energy chemicals. The object of this paper is, in a general way, to discuss the subject of chemical rocket propellants in such a way that the following five questions will be, in part at least, answered or recalled to the minds of this audience for additional deliberation.

Given the complexity of green public procurement, decisions are likely to be driven by bounded rationality. However, we know little about what determines supplier selection criteria in any given situation. This study explores buyer behavior when considering environmental criteria. We first conducted interviews and identified 12 operational procedures used by buyers. We then developed a survey to explore the use of these procedures. Our quantitative analysis suggests that public buyers are motivated by their belief that they can make a difference. This is independent of buyers' experience or gender. However, their occupational position and the nature of a procurement seem to influence how buyers seek information about environmental criteria and which information source(s) they use. The data suggest that four specific decision-making heuristics are associated with the selected operational procedures.

New educators may feel overwhelmed by the options available for engaging students through classroom participation. However, it may be helpful to recognize that participatory pedagogical systems often have constructivist roots. Adopting a constructivist perspective, our paper considers three meta-practices that encourage student participation: designing activities, leading others, and assessing peers. We explored the consequences of these meta-practices for important student outcomes, including content knowledge, engagement, self-efficacy, sense of community, and self-awareness. We found that different meta-practices were associated with different combinations of outcomes. This discovery demonstrates the benefit of studying meta- practices so as to reveal the nuanced effects that may arise from pedagogical choices. In addition, an understanding of meta-practices can help leadership educators to be more discerning and intentional in their course designs.

There is growing interest in using crop residues, particularly cereal straw, to replace fossil fuels in heat and electricity production. The purpose of the present study was to assess and compare the environmental impacts of straw production in two European Union countries, Poland and Finland.

The selected environmental impacts were greenhouse gas (GHG) emissions, biodiversity and soil physical quality. The latter was represented by the indicators of soil erosion and compaction. For biodiversity and erosion assessment, the authors used two methods that could be used with existing easily accessible data and thus did not require excessive fieldwork.

Compared to the fossil reference fuel, coal, straw production caused minimal GHG emissions in both of the subject countries. Biodiversity and erosion impacts were greater in Poland, while the potential risk of soil compaction caused by field traffic is greater in Finland.

The study provides insight into the impacts of bioenergy production on biodiversity and soil quality, of which there is currently limited knowledge.

This paper aims to numerically study the compositional flow of two- and three-phase fluids in one-dimensional porous media and to make a comparison between several upwind and central numerical schemes.

Implicit pressure explicit composition (IMPEC) procedure is used for discretization of governing equations. The pressure equation is solved implicitly, whereas the mass conservation equations are solved explicitly using different upwind (UPW) and central (CEN) numerical schemes. These include classical upwind (UPW-CLS), flux-based decomposition upwind (UPW-FLX), variable-based decomposition upwind (UPW-VAR), Roe’s upwind (UPW-ROE), local Lax–Friedrichs (CEN-LLF), dominant wave (CEN-DW), Harten–Lax–van Leer (HLL) and newly proposed modified dominant wave (CEN-MDW) schemes. To achieve higher resolution, high-order data generated by either monotone upstream-centered schemes for conservation laws (MUSCL) or weighted essentially non-oscillatory (WENO) reconstructions are used.

It was found that the new CEN-MDW scheme can accurately solve multiphase compositional flow equations. This scheme uses most of the information in flux function while it has a moderate computational cost as a consequence of using simple algebraic formula for the wave speed approximation. Moreover, numerically calculated wave structure is shown to be used as a tool for a priori estimation of problematic regions, i.e. degenerate, umbilic and elliptic points, which require applying correction procedures to produce physically acceptable (entropy) solutions.

This paper is concerned with one-dimensional study of compositional two- and three-phase flows in porous media. Temperature is assumed constant and the physical model accounts for miscibility and compressibility of fluids, whereas gravity and capillary effects are neglected.

The proposed numerical scheme can be efficiently used for solving two- and three-phase compositional flows in porous media with a low computational cost which is especially useful when the number of chemical species increases.

A new central scheme is proposed that leads to improved accuracy and computational efficiency. Moreover, to the best of authors knowledge, this is the first time that the wave structure of compositional model is investigated numerically to determine the problematic situations during numerical solution and adopt appropriate correction techniques.

Creating an engaging, inclusive, and supportive learning environment within higher education is challenging at the best of times. When considering refugees and learners who have been displaced from their home/region country due to war, this is paramount to enable continued learning. Team-based learning (TBL) is an active learning methodology whereby the learners take ownership of their learning and work within peer teams to deepen their learning through the application of knowledge. In the context of the above setting, TBL offers a number of key advantages over traditional didactic learning approaches to better support diverse student groups and aid learner integration. This chapter explores these advantages and details how TBL is not just a method of content delivery, but an approach which can bring about increased peer support (on campus and online), an increased sense of student belongingness and community, employability skills, and so on.

This chapter provides a review of existing research on learning gain and related topics in higher education. The methodology adopted is a form of systematic review. The origins and meaning of learning gain, and its relation to similar terms, are discussed. The ways in which learning gain has been applied in practice and in research are considered. The issues raised by this practice and research are examined, and the various criticisms made are reviewed. Some conclusions are then drawn.

As members of a team of bilingual preservice faculty in the South Texas borderlands, we have observed a consistent, pattern of inappropriate pedagogy offered to the emergent bilingual learners (EBLs) in the region’s inadequate PK-12 system, where subtractivist teaching practices and school policies undermined their academic development and their personal and professional identities as bilinguals and linguistic minorities. Our task is to teach our preservice students about best practices as we help them develop an awareness of themselves as bilingual, bi-literate professionals who can navigate within the accountability-driven school system and provide additive developmental learning opportunities to their emergent bilingual students.

In this chapter, we describe the experiences and findings from a five-year research project that employed an innovative approach to higher education pedagogy to teach 63 bilingual preservice students how to provide research-based, constructivist-oriented additive pedagogy to emergent bilinguals. Analysis of data from journals and focus group discussions suggest the development of the critical stance necessary for the development of an additive approach needed for the optimal development of emergent bilinguals. Although the study is limited to the specific context of South Texas US–Mexico border communities, the findings have implications for the preparation of bilingual education settings across the nation.