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IN Part I the motion of an aircraft, designated by the position‐tensor X, was considered relative to a fixed reference frame E. Now in our analysis of the motion of a wing, designated by the position‐tensor U, the relevant reference frame is X, though X is still free to move relative to E. The hinge on which the wing moves in the aircraft is denoted by the unit vector h, and for any specified hinge‐axis the components of h with respect to both U and X will have fixed values. The basic notation, following the principles adopted in Part I, Section (2), is therefore

The orientation of a rigid body is described by a position‐tensor, composed of three unit vector axes fixed in the body; rotation is effected by tensor transformations in which a rotational operator is a Cartesian matrix, formed from the co‐ordinates of the pivot axis and components of the angle of rotation; rotational sequences are represented by matrix products. Three practical applications are discussed: sequences of aircraft manoeuvres, which include composite rotations of roll and pitch, or roll, pitch and yaw, applied simultaneously; the variation of sweep, incidence and dihedral of a wing moving on any axis fixed in the aircraft; the direction of the pivot axis and the angle of rotation in the motion of a retractable undercarriage between two specified positions.

PART III The Motion of a Retractable Undercarriage THE methods developed in Part I, to describe the motion of a body moving on a fixed axis, enable the direction of the axis and the angle of rotation to be determined from two compatible positions of a component relative to a parent body. Graphical methods, such as that devised by Bailkowski, are available for finding the axis of rotation of an undercarriage when the extended and retracted positions are specified, but an analytical method will always give a more accurate solution than a graphical one, and it may at the same time be both shorter and simpler.

With an increasing urbanization trend over the last decades, urban agglomerations are facing different challenges that affect its inhabitants: pollution, traffic congestion, thriving population growth rates, and economic uncertainty. In the context of Latin America, where less than 20% of its inhabitants live in rural areas and with a projection to decrease to close to 10% by the year 2030, providing solutions to reduce the impact of this increase of population, on at least one of the issues, seems logical.

This study focuses on the urban logistics component to propose a classification method for homogeneous areas, using Factor Analysis (FA) and analysis of variance (ANOVA) as the main supporting tools. The proposed methodology builds up on the square kilometer (KM2) methodology developed by MIT Center for Transportation and Logistics, applying it in a neuralgic section of the downtown area of a mid-sized city in Latin America: Córdoba, Argentina. The selection was made considering the logistic restrictions, commercial density, and the relevance of the area for the city. Our proposed methodology uses relevant variables for urban logistics to perform the statistical analysis. The main goal is to develop a data-driven methodology to identify clusters to guide Córdoba's urban logistics policy and decision-making processes.

The results suggest a clear relationship between the different commercial activities and the location inside the area, splitting the area under study clearly into two main sections with similar overall characteristics and two subsections inside each one of them, which should be considered as a basis for further urban logistic analysis and implementation of specific best practices that fit the particular needs.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.

The announcement of their Annual Conference which has been made by the Library Association gives promise of a meeting of quite unusual interest and value. The programme has been shorn of unnecessary redundancies and every subject upon it should lead to fruitful discussion. The only point in connection with the programme which appears to demand consideration is whether in all cases the papers should be read. There are several objections. Such papers occupy a lot of time, are not sufficiently dramatic to be interesting in themselves, however valuable the subject matter may be, and too often it must be confessed they are read in a manner which induces somnolence rather than energetic discussion. It is the exchange of opinion across the floor that matters at a Conference, We hope, therefore, that in certain cases the method of taking papers as read and requiring their writers to speak to them briefly may be followed.

FROM time to time controversies arise as to the respective merits of two, or possibly more, solutions of a certain technical problem. These rage fiercely for a few years and then, usually, one system proves to be demonstrably better, and becomes almost universal. Thus the axial flow compressor is now universal for all but the smallest gas turbine aero‐engines. There is still an active discussion as to whether low‐voltage d.c. will be entirely superseded by 400 cycle a.c. At a recent conference on aircraft icing protection, mentioned in this issue, the relative merits of hot gas and electrical deicing were argued, as was the degree of automatic control which was desirable in a deicing system. In the field of aircraft auxiliary services the lead has for a long time been held by hydraulics, with electrical actuation challenging and pneumatics rather neglected, except for certain specialized applications. In an article in this issue Mr J. Wotton, of Hunting Aircraft, gives the findings of a project study on the possibilities of pneumatics, undertaken with the small twin jet airliner design known as the P 107 in mind.

In this chapter, the authors contribute toward building a better understanding of farmers’ responses to behavioral drivers of land-use decision by establishing an alternative analytical procedure, which can overcome various drawbacks suffered by methods currently used in existing studies. Firstly, our procedure makes use of spatially high-resolution data, so that idiosyncratic effects of physical environment drivers, e.g., soil textures, can be explicitly modeled. Secondly, we address the well-known censored data problem, which often hinders a successful analysis of land-use shares. Thirdly, we incorporate spatial error dependence (SED) and heterogeneity in order to obtain efficiency gain and a more accurate formulation of variances for the parameter estimates. Finally, the authors reduce the computational burden and improve estimation accuracy by introducing an alternative generalized method of moments (GMM)–quasi maximum likelihood (QML) hybrid estimation procedure. The authors apply the newly proposed procedure to spatially high-resolution data in England and found that, by taking these features into consideration, the authors are able to formulate conclusions about causal effects of climatic and physical environment, and environmental policy on land-use shares that differ significantly from those made based on methods that are currently used in the literature. Moreover, the authors show that our method enables derivation of a more effective predictor of the land-use shares, which is utterly useful from the policy-making point of view.

Sustainability is an emotional issue. It is also an issue that is gaining prominence in organizational agendas. In this chapter, we outline a model to explain how employees perceive change agents working to implement sustainability initiatives in organizations. Using this model, we argue that organizational support for sustainability can influence how employees respond to sustainability messages. We further argue that the intensity of emotions that change agents display, and how appropriate those emotions are within the organizational context, will influence how employees perceive those individuals and the success of their efforts to influence green outcomes.

We extend the Dual Threshold Model of emotions (DTM: Geddes & Callister, 2007) to assess the impact of displays of emotional intensity on achieving sustainability goals. Our model links emotional propriety to change agent success. By exploring variations of the DTM in terms of contextual factors and emotional intensity, our model elaborates on the dynamic nature of emotional thresholds.

Using our framework, change agents may be able to improve their influence by matching the emotional intensity of their messages to the relevant display rules for that organization. That is, change agents who are perceived to express emotion within the thresholds of propriety can enhance their success in implementing green outcomes.

This chapter examines sustainability initiatives at the interpersonal behavior level. We combine aspects of organizational behavior, emotion in organizations, and organizations and the natural environment to create a new model for understanding change agent success in corporate sustainability.

Special education in the USA is, in most respects, a 20th century phenomenon and is now governed primarily by federal legislation first enacted in 1975. The federal law in its most recent reauthorization (2004) continues to require a free appropriate public education (FAPE) for all students with disabilities, a full continuum of alternative placements (CAP) ranging from residential or hospital care to inclusion in general education, an individual education plan or program (IEP) for each student identified as needing special education, and placement in the least restrictive environment (LRE) that is thought best for implementing the IEP. Parents must be involved in the special education process. Approximately 14 percent of public school students were identified for special education in 2004–2005, but the number and percentage of students identified in most high-incidence categories as needing special education have declined in recent years (the total for all categories was about 8.5 percent of public school students in 2010). A variety of evidence-based interventions can be used to address the wide range of instructional and behavioral needs of students with disabilities and their families, including transition to further education or work, family services, and teacher education. Special education in the USA may find new sources of support and thrive or may become less common or be abandoned entirely due to criticism and withdrawal of support for social welfare programs of government.