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The last mile of parcel deliveries is a key process to service providers, with global costs that reach up to 70 billion euros per year. Moreover, due to urban population growth and to the rise of e-commerce, the importance of last-mile deliveries and its impacts to the environment and quality of life in cities tend to increase even more. This chapter proposes a more comprehensive methodology to assess alternative last-mile distribution strategies in terms of environmental and economic aspects and presents an application to the distribution of a postal company located in the city of Rio de Janeiro, Brazil. We evaluated the use of small electric vehicles (i.e., tricycles) in the last mile deliveries by assessing two scenarios: (1) the baseline scenario using a light commercial vehicle and (2) a scenario using electric tricycles. Results indicated that the use of electric tricycle is a more feasible alternative regarding the economic and environmental aspects as well as to maintain the service level of the company.

A PROBLEM which has attracted some attention since the advent of the tricycle undercarriage is that of the tendency to oscillate or “shimmy ” sometimes shown by the nose‐wheel, which is normally free to rotate about the vertical or castoring axis, subject to the restraint imposed by frictional or hydraulic dampers. Various attempts have been made to predict the amount of damping required to prevent the building‐up of a dangerous wobble; in the simplified investigation which follows it is believed that all the essential variables have been retained, and the basic character of the motion correctly reproduced.

This study aims to explore the association between the tricycle drivers’ personal attitude and perceived behavioral control and their entrepreneurial intention. Moreover, the study was conducted to determine whether such a relationship is moderated by structural support.

A total of 349 tricycle drivers in the Philippines were randomly selected and served as the respondents of this study. To determine if there is a significant relationship between the variables, structural equation modeling was used.

Tricycle drivers denoted that the more positive their perceived behavior control and personal attitude is, the greater their entrepreneurial intention is likely to be. Hence, the relationship of perceived behavioral control and personal attitude on entrepreneurial intention is moderated by perceived structural support.

By learning individuals’ perceived behavioral control, personal attitude and their entrepreneurial intention of specific classes of people, specifically tricycle drivers, it is possible to assess the feasibility of entrepreneurial efforts initiated by the government even before it is implemented, avoiding wastage of both times, resources and effort.

THE General Problem.—The inertia loading of a tricycle undercarriage presents a problem of considerable difficulty to designers. The type of tricycle under consideration has a pair of wheels not far behind the centre of gravity and a single wheel a considerable distance in front. Although such an undercarriage has special characteristics not possessed by an orthodox undercarriage with two main wheels, it has the same essential duties to perform: namely to absorb the kinetic energy associated with velocity of descent and to transmit the vertical retarding forces which reduce this velocity to zero. For these purposes, however, it has in the front and rear wheel units two distinct and in many ways independent shock‐absorbing systems, and the special problem is to assess the contributions made by each.

An article edited and prepared with comments by H. G. Conway, F.R.Ae.S., from a German report by Toennies and GoIIung (Research Group for Tricycle Undercarriages—Interim Report, 1944), issued by the Ministry of Supply as R.T.P./T.I.B. Translation No. G.D.C. 3E/3T

IF we trace the history of design in engineering, we can, in nearly every case we like to consider, point to a continuous development, a casting away of schemes which no longer meet new design requirements, and a continuous process of adaptation to extend the range of usefulness of the equipment in the field we survey.

IN the U.S.A. the development of the tricycle undercarriage has made very rapid progress. Low‐powered aeroplanes fitted with a nose‐wheel have exhibited remarkable properties and led to investigations on the application of this type of undercarriage to larger and faster machines. These investigations covered several years, as the influence of the nose‐wheel on modern high‐speed aeroplanes was not fully understood; a new principle of design had to be obtained for which complete calculation was not possible, since no details of the loadings were available (first methods proposed for reception of loads—1938) and finally there remained the difficulty of finding room for the nose‐wheel since the nose of the aircraft was utilized for other purposes. For these reasons firms sucli as Boeing and Glenn L. Martin have not produced any tricycle undercarriage design up to the present. On the other hand, almost all the firms in the neighbourhood of Los Angeles, which is the centre of production, have included nose‐wheels in their design and even for military aircraft it does not appear likely that the tail‐wheel will be used in any new design.

This study aims to investigate female commercial drivers in the Lagos metropolis. The study sought to know the circumstances that motivated women to venture into commercial driving; the experiences they encounter whilst engaging with other stakeholders in the public space; the dimension of the conflict between work and family, and the coping strategies used and finally, the health concerns of female commercial drivers.

The study adopted a cross-sectional design and a qualitative method of data collection. An in-depth interview guide was used to elicit information from 18 female drivers drawn from three sectors of commercial transportation in Lagos State.

It was found that the major motivation for engaging in commercial driving is the need for survival and family support; although participants acknowledged that they cannot be in the profession for a long time. Married women had less time to engage in commercial driving due to other family responsibilities. Women drivers have experienced mixed reactions from other road users. Commercial driving is physically demanding and poses threat to the health of female commercial drivers.

The findings highlight the circumstances behind women participating in commercial driving. Despite the challenges encountered in this course of this activity, they are still bent on continuing because of the need to take care of their children, a majority of their spouses are not fully contributing to the maintenance of the home.

WITH typical Teutonic thoroughness the article which we publish in translation form from Luftwissen this month, contains as complete data as is probably possible on the evolution of the tricycle undercarriage, with particular reference to its development in the United States. Great credit is due to Mr. Weick for his vision in foreseeing the advantages of this old but long‐disused form of undercarriage. It is true that he was in his inception chiefly concerned with the improvement of landing conditions for the inexperienced amateur pilot and can scarcely have envisaged the potentialities—and how the small ball he started would increase in size and the distance to which it would roll.

THE take‐off of a tricycle‐undercarriage aeroplane has been carefully analyzed and the effects of slipstream included. Wheel position relative to the C.G. is shown to have an important effect on the take‐off run and flaps may or may not adversely affect the run. Elevator power should be high yet light enough to provide adequate control at the take‐off speed.