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Article
Publication date: 1 January 1993

S.M. El‐Sawy, F.A. Abdel Mohdy and M.A. Abd El‐Ghaffar

Some anticorrosive water‐borne paint formulations were prepared. These formulations based on zinc phosphate, zinc tetroxy chrornate and barium metaborate as inhibitive pigments…

Abstract

Some anticorrosive water‐borne paint formulations were prepared. These formulations based on zinc phosphate, zinc tetroxy chrornate and barium metaborate as inhibitive pigments with acrylate emulsions in absence and in presence of a water repellent type emulsion. The corrosion protective properties as well as the physico‐mechanical characteristics of painted films were studied and evaluated. Promising results were obtained which urge us to pay attention to the utilisation of these types of water‐borne paints from the point of view of econmy and safety.

Details

Pigment & Resin Technology, vol. 22 no. 1
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 May 1939

A structural element of an aeroplane comprises a sheath of thin sheet metal and a wooden core fitting closely within and completely filling the sheath, the core being held under…

Abstract

A structural element of an aeroplane comprises a sheath of thin sheet metal and a wooden core fitting closely within and completely filling the sheath, the core being held under endwise compression by means of metal discs or plugs forced into the ends of the sheath. In one form, Figs. 14 and 18, a sheath 4 is formed by bending a metal strip into tubular form and welding along overlapping edges, a core 5 being then inserted. Alternatively the metal strip may be wrapped round a core by rolling or drawing, or the sheath may be a plain or butt welded lube. Discs or plugs 7, Fig. 18, are welded to the sheath. An aeroplane incorporating elements formed as above described comprises stub wings 2 formed integrally with the structure of fuselage 1, Fig. 2, and main wing portions 3. Each wing includes three spars a, b, c, Fig. 3, each constituted by booms 8, 9, Fig. 12, connected by vertical struts 13 and diagonal braces 14 secured to the booms and to each other by gussets. The spars are interconnected by upper rib elements 10 and lower rib elements 11 having outwardly turned flanges 18, for attachment of the skin 12 and notched as shown to clear the booms to which they are secured by welded angle gussets. Supplementary booms 19 extend the full length of the wings, Figs. 3 and 4, and are disposed one at each side of spar b and supplementary booms 20 are arranged between booms 19 and spars a and c, these booms extending only part of the span, Fig. 3. Midway between booms 9 of spars a and b and of spars b and c, respectively, are disposed supplementary booms 21 extending outwardly beyond booms 20 but terminating short of the full span. Booms 9, 19, 20, 21 and upper and lower rib elements are interconnected by diagonal braces 22, Fig. 4, in the planes of the ribs. In addition, pairs of diagonal braces 23 are arranged as shown in Fig. 3 between booms 19 and 21 at the mid‐section of the wing. In the root bay of the wing, Fig. 3, booms 20, 21 are connected by pairs of braces 24 and booms 19, 21 by pairs of braces 25, Figs. 3 and 6, the latter being stabilized by struts 26. All connexions are effected by welded gusset plates. The internal structureof thestubwings 2 which is continuous through the fuselage, Fig. 2, is of the same construction as that of the root bays of the main wings and the connexion between the stub and main wings is by angle strips 30, Fig. 7, bent to the wing contour and secured one to the stub and one to the outer wing by welding the inner flange between the wing skin 12 and internal structure, the strips being secured to one another by bolts 32 passing through out‐turned flanges 31 of the strips and the margin of a bulkhead 29. Upper and lower spar booms, longerons, and gussets of each wing part merely abut on the bulkhead 29. The nose and tail portions of the wing comprise rib parts 33, 36, respectively, Fig. 4, secured to front and rear spars at rib attachment points and channel stringers 35, 37, respectively, Fig. 3, to which and to the rib parts skin 12 is spot welded. Wing tip 38 is formed by welding the overlapped edges of a shaped sheet metal shell to the main wing body. The fuselage frame, Fig. 16, 17, incorporates composite wood‐metal members and comprises longerons 39, vertical and transverse struts 40, and diagonal struts 41, secured together by spot welded angle plates 42. The corner angles are reinforced by braces 43 attached to the struts by welded‐on plates 44.

Details

Aircraft Engineering and Aerospace Technology, vol. 11 no. 5
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 January 1934

AIRCRAFT of the type known under the Registered Trade Mark “Autogiio,” have means for controllably tilting the rotor axis in relation to the body in one or more substantially…

Abstract

AIRCRAFT of the type known under the Registered Trade Mark “Autogiio,” have means for controllably tilting the rotor axis in relation to the body in one or more substantially vertical planes about real or virtual pivot axes, any such pivot axis being located above the centre of gravity of the aircraft, below the point of intersection of the rotor axis with the projection of the line of resultant aerodynamic action of the rotor on a plane containing both the rotor axis and the shortest distance between the rotor axis and the pivot axis, and offset from the rotor axis in the direction of the aerodynamic reaction line. Figs. 2 and 5 show diagrammatically an aircraft having a body b, a rotor comprising blades r, r, connected by horizontal hinges a, a, to a rotor hub having an axis of rotation 0, 0. Lines 0–0, 1–1, 2–2, etc., represent the projections on the plane of the paper of the aerodynamic reaction lines corresponding to successively reduced angles of incidence of the rotor, line 0–0 representing the reaction line for an angle of incidence of 90 deg. corresponding to vertical descent, line 5–5 representing that corresponding to a small angle of incidence corresponding to maximum flight speed. These projection lines intersect at a focal point f1, the height of which above the hinges a, a depends upon the degree of separation thereof, this height being zero when the hinges a, a are coaxial and intersect the axis of rotation. The transverse axis about which the rotor may be tilted is shown at p2 and is disposed below the point f1 and forward of the axis of rotation 0, 0. In the limiting case where the hinges a, a are coaxial p2 may pass through the point of intersection of the hinges with the axis 0–0. Fig. 5 shows how the longitudinal pivot axis p5 for lateral tilting of the rotor is displaced from the axis of rotation 0–0 in the direction of the aerodynamic reaction line, i.e., in the direction of the re‐treating blade. The transverse pivot p2 for longitudinal rotor tilting is located rearwardly of the centre of gravity, the perpendicular from the centre of gravity on the pivot making an angle of the order of 6 deg. with the perpendicular to the longitudinal body axis. Means may also be provided for bodily displacing the rotor longitudinally of the aircraft whereby the attitude of the body to the line of flight may be controlled in the plane of symmetry, independently of the flying speed and of the position of the centre of gravity. In one embodiment, Fig. 6, a pyramid of struts 36 supports a rotor comprising blades 38 secured to a hub 37 by horizontal pivots 39, links 40, and vertical pivots 41. Hub 37 is mounted on an axis member 78, Figs. 9 and 10, pivotally mounted on pyramid 36 by means of a transverse pivot 42 and a longitudinal pivot 43, Fig. 8. Pyramid struts 36 are bolted to an apex member 71 incorporating a fork 72, Fig. 10, carrying transverse pivot 42 on which is rotatably mounted an intermediate member incorporating an offset backward projection constituting the longitudinal pivot 43 and a downward projection 76 which serves to limit rocking of member 74 about the pivot 42 by co‐operation with the sides of a shot 71x formed in apex member 71. Rocking movement of axis member 78 in pivot 43 is limited by integral lugs 80 which embrace the projection 76. Movements of part 74 about pivot 42 and of axis member 78 about pivot 43 are damped by spring‐loaded friction discs 148, 153 respectively, the pressure on which may be varied by adjusting their respective nuts 151, 156. As shown in Fig. 9, an internal expanding rotor brake and rotor starting gear are associated with the axis member 78, the latter gear including a dog clutch permitting over‐running of the rotor with respect to the drive shaft. Means for controlling the rotor tilting movements comprise levers 48, 52 respectively associated with the intermediate member 74 and the axis member 78. Lever 48 is coupled to a bell crank 46, Fig. 6, by a rod 47, and lever 52 is coupled to a lever 50, Fig. 8, on a longitudinal rock shaft 49 by rod 51, bell crank 46 and rock shaft 49 being operated by a conveniently arranged control column 44. Rods 47, 51 are tubular and are connected to their respective levers 48, 52 by resilient connections comprising columns of rubber rings 106, Fig. 9, which bear against abutments 107 fixed in the bore of the rod and against a collar 108 formed on a slidable rod 109 which is connected to the operating lever by a forked shackle 110, in the case of rod 47, and by a shackle 111 and an eyed swivel 112, Fig. 10, in the case of rod 51. Means are provided for imposing an elastic bias on either control: these comprise in the case of the fore‐and‐aft control two lengths 116 of shock absorber elastic, Fig. 11, coupled at one end to a lever 115 on shaft 113 of bell crank 46, and at the other by cables 117 to an adjustable lever 119 working in a quadrant 120. Similarly, shock absorbers 123 are coupled to a lever 122 on rock shaft 49 and are connected by cables 124, Fig. 12, passed round pulleys 126 to a lever 127 mounted on a subsidiary rock shaft 128, the angular position of which is controlled by a ratchet lever 129, Fig. 11. Shackles 118 are adjustable for varying the initial stress in elastics 116 and turnbuckles 125 are placed in the run of cables 124. In addition to control column 44, a rudder bar 55 is provided operating a rudder 54, Fig. 6, and a steerable tail wheel 64, and a lever 62 for adjusting a tail plane 57. All these controls may be locked in any adjusted position, lever 62 by a ratchet 63 and the remainder by means of friction clamps 141, 142, 143 respectively, Figs. 11 and 12. Clamp 141 locks a slotted lever 140 fast on rock shaft 49 to a fixed fuselage member. Similarly clamp 135 co‐operates with a slotted plate 134, linked by rod 133 to a lever, 132, on rock shaft 113. Clamp 143 co‐operates with a slotted plate 142, inserted in the run of a rudder cable 56x.

Details

Aircraft Engineering and Aerospace Technology, vol. 6 no. 1
Type: Research Article
ISSN: 0002-2667

Book part
Publication date: 1 November 2007

Irina Farquhar and Alan Sorkin

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative…

Abstract

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Details

The Value of Innovation: Impact on Health, Life Quality, Safety, and Regulatory Research
Type: Book
ISBN: 978-1-84950-551-2

Book part
Publication date: 4 April 2016

Farley Grubb

The British North American colonies were the first western economies to rely on legislature-issued paper monies as an important internal media of exchange. This system arose…

Abstract

The British North American colonies were the first western economies to rely on legislature-issued paper monies as an important internal media of exchange. This system arose piecemeal. In the absence of banks and treasuries that exchanged paper monies at face value for specie monies on demand, colonial governments experimented with other ways to anchor their paper monies to real values in the economy. These mechanisms included tax-redemption, land-backed loans, sinking funds, interest-bearing notes, and legal tender laws. I assess and explain the structure and performance of these mechanisms. This was monetary experimentation on a grand scale.

Details

Research in Economic History
Type: Book
ISBN: 978-1-78635-276-7

Keywords

Book part
Publication date: 23 October 2023

Glenn W. Harrison and J. Todd Swarthout

We take Cumulative Prospect Theory (CPT) seriously by rigorously estimating structural models using the full set of CPT parameters. Much of the literature only estimates a subset…

Abstract

We take Cumulative Prospect Theory (CPT) seriously by rigorously estimating structural models using the full set of CPT parameters. Much of the literature only estimates a subset of CPT parameters, or more simply assumes CPT parameter values from prior studies. Our data are from laboratory experiments with undergraduate students and MBA students facing substantial real incentives and losses. We also estimate structural models from Expected Utility Theory (EUT), Dual Theory (DT), Rank-Dependent Utility (RDU), and Disappointment Aversion (DA) for comparison. Our major finding is that a majority of individuals in our sample locally asset integrate. That is, they see a loss frame for what it is, a frame, and behave as if they evaluate the net payment rather than the gross loss when one is presented to them. This finding is devastating to the direct application of CPT to these data for those subjects. Support for CPT is greater when losses are covered out of an earned endowment rather than house money, but RDU is still the best single characterization of individual and pooled choices. Defenders of the CPT model claim, correctly, that the CPT model exists “because the data says it should.” In other words, the CPT model was borne from a wide range of stylized facts culled from parts of the cognitive psychology literature. If one is to take the CPT model seriously and rigorously then it needs to do a much better job of explaining the data than we see here.

Details

Models of Risk Preferences: Descriptive and Normative Challenges
Type: Book
ISBN: 978-1-83797-269-2

Keywords

Book part
Publication date: 20 October 2015

Mohammad Shamsuddoha

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured…

Abstract

Contemporary literature reveals that, to date, the poultry livestock sector has not received sufficient research attention. This particular industry suffers from unstructured supply chain practices, lack of awareness of the implications of the sustainability concept and failure to recycle poultry wastes. The current research thus attempts to develop an integrated supply chain model in the context of poultry industry in Bangladesh. The study considers both sustainability and supply chain issues in order to incorporate them in the poultry supply chain. By placing the forward and reverse supply chains in a single framework, existing problems can be resolved to gain economic, social and environmental benefits, which will be more sustainable than the present practices.

The theoretical underpinning of this research is ‘sustainability’ and the ‘supply chain processes’ in order to examine possible improvements in the poultry production process along with waste management. The research adopts the positivist paradigm and ‘design science’ methods with the support of system dynamics (SD) and the case study methods. Initially, a mental model is developed followed by the causal loop diagram based on in-depth interviews, focus group discussions and observation techniques. The causal model helps to understand the linkages between the associated variables for each issue. Finally, the causal loop diagram is transformed into a stock and flow (quantitative) model, which is a prerequisite for SD-based simulation modelling. A decision support system (DSS) is then developed to analyse the complex decision-making process along the supply chains.

The findings reveal that integration of the supply chain can bring economic, social and environmental sustainability along with a structured production process. It is also observed that the poultry industry can apply the model outcomes in the real-life practices with minor adjustments. This present research has both theoretical and practical implications. The proposed model’s unique characteristics in mitigating the existing problems are supported by the sustainability and supply chain theories. As for practical implications, the poultry industry in Bangladesh can follow the proposed supply chain structure (as par the research model) and test various policies via simulation prior to its application. Positive outcomes of the simulation study may provide enough confidence to implement the desired changes within the industry and their supply chain networks.

Details

Sustaining Competitive Advantage Via Business Intelligence, Knowledge Management, and System Dynamics
Type: Book
ISBN: 978-1-78560-707-3

Keywords

Book part
Publication date: 24 August 2011

Morten H. Abrahamsen

The study here examines how business actors adapt to changes in networks by analyzing their perceptions or their network pictures. The study is exploratory or iterative in the…

Abstract

The study here examines how business actors adapt to changes in networks by analyzing their perceptions or their network pictures. The study is exploratory or iterative in the sense that revisions occur to the research question, method, theory, and context as an integral part of the research process.

Changes within networks receive less research attention, although considerable research exists on explaining business network structures in different research traditions. This study analyzes changes in networks in terms of the industrial network approach. This approach sees networks as connected relationships between actors, where interdependent companies interact based on their sensemaking of their relevant network environment. The study develops a concept of network change as well as an operationalization for comparing perceptions of change, where the study introduces a template model of dottograms to systematically analyze differences in perceptions. The study then applies the model to analyze findings from a case study of Norwegian/Japanese seafood distribution, and the chapter provides a rich description of a complex system facing considerable pressure to change. In-depth personal interviews and cognitive mapping techniques are the main research tools applied, in addition to tracer studies and personal observation.

The dottogram method represents a valuable contribution to case study research as it enables systematic within-case and across-case analyses. A further theoretical contribution of the study is the suggestion that network change is about actors seeking to change their network position to gain access to resources. Thereby, the study also implies a close relationship between the concepts network position and the network change that has not been discussed within the network approach in great detail.

Another major contribution of the study is the analysis of the role that network pictures play in actors' efforts to change their network position. The study develops seven propositions in an attempt to describe the role of network pictures in network change. So far, the relevant literature discusses network pictures mainly as a theoretical concept. Finally, the chapter concludes with important implications for management practice.

Details

Interfirm Networks: Theory, Strategy, and Behavior
Type: Book
ISBN: 978-1-78052-024-7

Keywords

Book part
Publication date: 8 April 2005

Fredrik von Corswant

This paper deals with the organizing of interactive product development. Developing products in interaction between firms may provide benefits in terms of specialization…

Abstract

This paper deals with the organizing of interactive product development. Developing products in interaction between firms may provide benefits in terms of specialization, increased innovation, and possibilities to perform development activities in parallel. However, the differentiation of product development among a number of firms also implies that various dependencies need to be dealt with across firm boundaries. How dependencies may be dealt with across firms is related to how product development is organized. The purpose of the paper is to explore dependencies and how interactive product development may be organized with regard to these dependencies.

The analytical framework is based on the industrial network approach, and deals with the development of products in terms of adaptation and combination of heterogeneous resources. There are dependencies between resources, that is, they are embedded, implying that no resource can be developed in isolation. The characteristics of and dependencies related to four main categories of resources (products, production facilities, business units and business relationships) provide a basis for analyzing the organizing of interactive product development.

Three in-depth case studies are used to explore the organizing of interactive product development with regard to dependencies. The first two cases are based on the development of the electrical system and the seats for Volvo’s large car platform (P2), performed in interaction with Delphi and Lear respectively. The third case is based on the interaction between Scania and Dayco/DFC Tech for the development of various pipes and hoses for a new truck model.

The analysis is focused on what different dependencies the firms considered and dealt with, and how product development was organized with regard to these dependencies. It is concluded that there is a complex and dynamic pattern of dependencies that reaches far beyond the developed product as well as beyond individual business units. To deal with these dependencies, development may be organized in teams where several business units are represented. This enables interaction between different business units’ resource collections, which is important for resource adaptation as well as for innovation. The delimiting and relating functions of the team boundary are elaborated upon and it is argued that also teams may be regarded as actors. It is also concluded that a modular product structure may entail a modular organization with regard to the teams, though, interaction between business units and teams is needed. A strong connection between the technical structure and the organizational structure is identified and it is concluded that policies regarding the technical structure (e.g. concerning “carry-over”) cannot be separated from the management of the organizational structure (e.g. the supplier structure). The organizing of product development is in itself a complex and dynamic task that needs to be subject to interaction between business units.

Details

Managing Product Innovation
Type: Book
ISBN: 978-1-84950-311-2

Abstract

Details

Transportation and Traffic Theory in the 21st Century
Type: Book
ISBN: 978-0-080-43926-6

1 – 10 of over 26000