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The main idea is the comparison between composites including natural fibres (such as the linoleum fibres) and typical composites including carbon fibres or glass fibres. The comparison is proposed for different structures (plates, cylinders, cylindrical and spherical shells), lamination sequences (cross-ply laminates and sandwiches with composite skins) and thickness ratios. The purpose of this paper is to understand if linoleum fibres could be useful for some specific aerospace applications.

A general exact three-dimensional shell model is used for the static analysis of the proposed structures to obtain displacements and stresses through the thickness. The shell model is based on a layer-wise approach and the differential equations of equilibrium are solved by means of the exponential matrix method.

In qualitative terms, composites including linoleum fibres have a mechanical behaviour similar to composites including glass or carbon fibres. In terms of stress and displacement values, composites including linoleum fibres can be used in aerospace applications with limited loads. They are comparable with composites including glass fibres. In general, they are not competitive with respect to composites including carbon fibres. Such conclusions have been verified for different structure geometries, lamination sequences and thickness ratios.

The proposed general exact 3D shell model allows the analysis of different geometries (plates and shells), materials and laminations in a unified manner using the differential equilibrium equations written in general orthogonal curvilinear coordinates. These equations written for spherical shells degenerate in those for cylinders, cylindrical shell panels and plates by means of opportune considerations about the radii of curvature. The proposed shell model allows an exhaustive comparison between different laminated and sandwich composite structures considering the typical zigzag form of displacements and the correct imposition of compatibility conditions for displacements and equilibrium conditions for transverse stresses.

To examine communities that temporarily demonstrated successful social and economic success, but regressed, or may have cycled through periods marked by unusual success and unusual failure.

The authors analyse events in two communities that have experienced disentrepreneurship.

The authors attribute three main forces accountable for community disentrepreneurship: a failure in community leadership that allows the continuation of path dependent patron‐client relationships, peripheralisation resulting from both geographical and infrastructure constraints, and failure to adequately diversify the economic environment. It is believed that further study of communities that have experienced such cycles is both warranted, and essential.

A useful source of information for academics as well as for town planners, policy‐makers and economists.

This paper addresses a largely overlooked area of the landscape.

Reinforced Plastics have been widely used in the Aircraft Industry over the past ten years, but its application is still treated as something of a special field. The purpose of these notes is to introduce the subject to the Drawing Office and to set simply before the draughtsman another engineering material. The use of plastics is not recommended for primary structure at present, due to insufficiency of test results, but for secondary structure they may offer advantages in robustness and non‐corrodibilily over light alloy, with increase in weight, and sometimes with less weight. In complex shaped fairings, the ease of forming of reinforced plastics enables the component to be moulded as an integral structure, thus reducing fabrication and consequently costs. The reduction in the number of parts means less weight and the resulting structure is often intrinsically stronger. They also have many applications where their particular properties, such as electrical properties, non‐corrodibility, acid resistance or high specific tensile strength are desirable. Typical applications for the material are summarized in TABLE I together with reasons for their use.

Oertling have produced an informative pamphlet on their digital analytical balances. It includes the basic features e.g. tare, read‐out, design, technical data, a clear diagram and a list of over‐seas agents. These models complete the comprehensive ‘R’ series of 7 digital balances.

The purpose of this paper is to propose a comparative study between different structures composed of fiber-reinforced composite materials. Plates, cylinders and cylindrical and spherical shell panels in symmetric 0°/90°/0° and antisymmetric 0°/90°/0°/90° configurations are analyzed considering carbon fiber, glass fiber and linoleum fiber reinforcements.

A free vibration analysis is proposed for different materials, lamination sequences, vibration modes, half-wave numbers and thickness ratios. Such an analysis is conducted by means of an exact three-dimensional shell model which is valid for simply supported structures and cross-ply laminations. The employed model is based on a layer-wise approach and on three-dimensional shell equilibrium equations written in general orthogonal curvilinear coordinates.

The proposed study confirms the well-known superiority of the carbon fiber-reinforced composites. Linoleum fiber-reinforced composites prove to be comparable to glass fiber-reinforced composites in the case of free vibration analysis. Therefore, similar frequencies are obtained for all the geometries, thickness ratios, laminations sequences, vibration modes and a large spectrum of half-wave numbers. This partial conclusion needs further confirmations via static, buckling and fatigue analyses.

An exact three-dimensional shell model has been used to compare several geometries embedding carbon fiber composites and natural fiber composites.

The animal and vegetable oils, fats, and waxes provide vital raw materials for a large number of industries. Soap, paint, foodstuffs, textiles, leather, and linoleum are but a few of the diversity of products which employ one or more of this large class of natural bodies.

To examine empirically a previously overlooked aspect of entrepreneurship: community “dis‐entrepreneurship”. Through the lens of political and historical theory, the authors propose learning from unusual circumstances of failure in order to inform social policy regarding factors that facilitate community entrepreneurship.

The paper draws on political and economic theory, formulating propositions that are tested using interpretive methods.

Strong patron‐client relations were found to negatively impact the formation of diversity and meritocracy necessary for entrepreneurial environments to thrive. They also account for an inward orientation that negatively influenced investments in infrastructure. Path dependent processes were found to hold sway regarding the stability of political/social norms.

This is the first paper of which the authors are aware that considers issues related to community dis‐entrepreneurship. The paper highlights the importance of effective community leadership.

This article aims to summarize Norwegian cleaning‐related research to give an overview of the knowledge held today and to categorize the approaches used.

The research is based on an extensive literature search. Research contributions from 1814 until 2009 were studied, even though the main findings are from 1950. The different disciplines contributing to research are mapped and the contributions are categorized based on different research approaches, namely positivism, interpretivism, realism and idealism.

Norwegian cleaning‐related research experienced a burst in publications from the 1990s. The majority of Norwegian cleaning‐related research has been positivistic, mostly based on realism. The least common approach used was interpretivism‐idealism and interviews were the most frequently used method in interpretivisitc contribution. The article indicates a need for further broadening in research methods.

Through categorizing existing knowledge the article will help when searching for information and thus stimulate more research as limited research exists within the field.

The paper represents a summary of the knowledge status in cleaning with a Norwegian perspective. It is believed that the general picture also has international relevance.

Few researchers have investigated cleaning work from the perspective of cleaning personnel. It should also be noted that there has been little focus on the usability of buildings for cleaning personnel.

This article may be the first historical overview of Norwegian cleaning‐related research.

The Secretary of State after consultation with the Furniture and Timber Industry Training Board and with organisations and associations of organisations appearing to be representative respectively of substantial numbers of employers engaging in the activities hereinafter mentioned and of substantial numbers of persons employed in those activities and in exercise of her powers under section 9 of the Industrial Training Act 1964 and of all other powers enabling her in that behalf hereby makes the following Order:—

The Minister of Labour (hereinafter referred to as “the Minister”) after consultation with organisations and associations of organisations appearing to be representative respectively of substantial numbers of employers engaging in the activities hereinafter mentioned and of substantial numbers of persons employed in those activities and by virtue of the powers conferred on him by section 1 of, and paragraphs 1 and 7 of the Schedule to, the Industrial Training Act 1964(a) (hereinafter referred to as “the Act”) and of all other powers enabling him in that behalf makes the following Order:—