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Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

THE variation of full throttle engine brake horsepower with altitude at constant rotational speed is a matter of great importance to aircraft designers and those concerned with the measurement of aircraft performance. For the former its main importance probably lies in the design of aeroplanes intended for high altitude use where accurate knowledge of the engine power available is of paramount importance in the evolution of a successful aircraft. In the measurement of aircraft performance it is necessary to reduce the observed results at non‐standard atmospheric conditions to those obtaining under the chosen standard conditions, and for this it is essential that the variation of engine power with altitude is well established.

IT cannot be denied that, in spite of the popular interest and enthusiasm and the high speed attained, the Schneider Trophy contest was in many ways a failure. It is a regrettable fact that France, who was the pioneer of the seaplane and who won the first race in 1913, has never since provided the winner, and since 1920 has not brought a machine to the starting line. This year she took a belated interest, but started her effort far too late to have any chance of making a welcome reappearance. America, after setting the example of Government participation with officially financed machines and Service pilots, got tired after 1926, just as Italy and other Governments began to wake up. This year the American entry, designed apparently as a spare‐time job in the Navy Yard, was also started too late, and when it appeared proved unsatisfactory and was withdrawn. This left Italy and Great Britain again as the only participants; but, in spite of the two years' interval, neither of them was really ready. Italy suffered serious setbacks during the preliminary trials of what was probably her fastest, though least seaworthy, machine, and on the day of the race had but one engine and one seaplane thoroughly in trimonly unfortunately they did not happen to be combined in the same machine. One of Great Britain's entries was suffering from fuel‐supply troubles not solved until a day or two after the race; while the other, which did, however, compete, was the subject of float experiments until almost the last minute. Finally, the weather for a week or two prior to September 6 was almost always unsuitable so that both teams had to start short of practice.

IN 1929 a subcommittee was formed, by the Aeronautical Research Committee, to investigate the subject of aircraft noise. Various aspects of the work have received attention, and the present paper is an attempt to summarise the general conclusions in a form suitable for the aircraft industry, without reference to the results of the investigations themselves.

This study aimed to address a gap in subcontractor management by focusing on previously unexplored complexities surrounding subcontractor management in developing countries. While past studies concentrated on selection and relationships, this study delved into how effective subcontractor management impacts project success.

This study used the Bayesian Network analysis approach, through a meticulously developed questionnaire survey refined through a piloting stage involving experienced industry professionals. The survey was ultimately distributed among participants based in Accra, Ghana, resulting in a response rate of approximately 63%.

The research identified diverse components contributing to subcontractor disruptions, highlighted the necessity of a clear regulatory framework, emphasized the impact of financial and leadership assessments on performance, and underscored the crucial role of main contractors in Integrated Project and Labour Cost Management with Subcontractor Oversight and Coordination.

Previous studies have not considered the challenges subcontractors face in projects. This investigation bridges this gap from multiple perspectives, using Bayesian network analysis to enhance subcontractor management, thereby contributing to the successful completion of construction projects.

In this paper we describe the process of developing and implementing a knowledge management system for the Spanish judicial domain. Spanish judges, especially newly‐recruited ones, hold a solid background of theoretical legal knowledge, but are much less familiar with the judicial knowledge of the more senior judges acquired from everyday practice and case resolution. The aim of this development is to capture and model these two aspects of judicial knowledge – theoretical and practical – for knowledge browsing and retrieving.

Semantic web technologies are applied to feed a question‐answering system based on ontologies of professional legal knowledge (OPLK).

There is a kind of specific legal knowledge, which belongs properly to the expert domain, not being captured by current legal core ontologies, i.e. Judges require clues, hints or well‐grounded practical guidelines that refer to the problem they have before them when they put a question or start the query. A scalable and useful frequently‐asked questions system should have a simple, natural language interface, work in a real time environment, and the questions included in the system should be of high quality and reflect the current situation.

The final system will enable the users to ask queries in natural language and obtain answers, which are supported by legal documents stored in specialized legal databases. Special care is taken regarding usability issues, in order to ensure the highest user satisfaction.

The purpose of this paper is to address the increasingly important issue of the impact of product design on supply chain risk management in an era of global supply arrangements. The need to include product design considerations in the development of global supply chain strategies is highlighted.

The research methodology is based on an in‐depth longitudinal case study of a major UK retailer. Data collection tools included observation of supplier meetings/workshops, semi‐structured interviews and access to key company documentation and archives.

This paper provides a framework for design‐led supply chain risk management and thus presents a case for recognising design as more than a creative function but as a platform to manage risk in supply chains.

The empirical research reported in this paper is specific to the clothing manufacturing and fashion retail industry. Though the findings will most likely apply to all industries and supply chains where design has an integral role and plays an important part in the competitiveness of the final product, there would be benefit in extending the research into other sectors.

The increased trends to outsourcing and offshore sourcing and the elimination of trade barriers have added to the competitive pressures faced by clothing retailers, hence frameworks to manage supply chain risks are significant to the survival of companies from this sector.

Whilst there is a growing literature in the field of supply chain risk there is less empirical evidence providing practical examples of the impact of product design on risk. Design‐led risk management offers a novel approach to mitigating supply chain risk.

This study aims to focus on exploring the construction productivity of building projects under the influence of potential factors. The three primary purposes are (1) determining critical factors affecting construction productivity; (2) identifying causal relationship and occurrence probability of these factors to develop a Bayesian network (BN) model; and (3) validating the accuracy of predictions from the proposed BN model via a case study.

A conceptual framework that includes three performance stages was used. Twenty-two possible factors were screened from a comprehensive literature review and evaluated through expert opinions. Data were collected using a structured questionnaire-based survey and case-study-based survey. The sampling methods were based on non-probability sampling.

Worker characteristic-related factors significantly affect labour productivity for a construction task. Construction productivity is dominated by the working frequency of workers (overtime), complexity of the task, level of technology application and accidents. Labour productivity is defined as nearly 50% of the baseline productivity using the BN model created by the caut 2sal relationship and probability of factors. The prediction error of the BN model was 6.6%, 10.0% and 9.3% for formwork (m²/h), reinforcing steel (ton/h) and concrete (m³/h), respectively.

The evaluation or prediction of productivity performance has become a necessary topic for research and practice.

Managers and practitioners in the construction sector can utilise the outcome of this study to create good productivity management policies for their prospective projects.

Worker-related characteristics are dominant among critical factors affecting labour productivity for a construction task; the proposed BN-based predictive model is built based on these critical factors. The BN approach is highly accurate for construction productivity prediction. The findings of this study can fill gaps in the construction management body of knowledge when modelling construction productivity under the effects of multiple factors and using a simple probabilistic graphic tool.

Examines the relationship between organizational learning and product design management while, at the same time, analysing the repercussions they may have on performance, in the Spanish ceramic tile sector. A comparative case study of four companies from this sector enabled the construction of a theoretical model, which linked the factors that facilitate organizational learning, in the context of product design management, with the activities of this practice. In this model, 14 factors are seen as being essential to the existence of organizational learning and may be divided into two groups: one related to the activities that have to do with the conceptual‐analytical phase of the product design process, and the other linked to the activities related to the creative‐technical phase. All these factors are positively associated with efficient product design management and with improved business performance.