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This paper presents the second-generation estimates for the Italian engineering industry in 1911, a year documented both by the customary demographic census, and the first industrial census. The first part of this paper uses the census data to estimate the industry’s value added, sector by sector; the second further disaggregates each sector by activity, and estimates the value added, employment, physical product, and metal consumption of each one. A third, concluding section dwells on the dependence of cross-section estimates on time-series evidence. Three appendices detail the specific algorithms that generate the present estimates; a fourth, a useful sample of firm-specific data.

Digital twin (DT) is an emerging technology that enables sophisticated interaction between physical objects and their virtual replicas. Although DT has recently gained significant attraction in both industry and academia, there is no systematic understanding of DT from its development history to its different concepts and applications in disparate disciplines. The majority of DT literature focuses on the conceptual development of DT frameworks for a specific implementation area. Hence, this paper provides a state-of-the-art review of DT history, different definitions and models, and six types of key enabling technologies. The review also provides a comprehensive survey of DT applications from two perspectives: (1) applications in four product-lifecycle phases, i.e. product design, manufacturing, operation and maintenance, and recycling and (2) applications in four categorized engineering fields, including aerospace engineering, tunneling and underground engineering, wind engineering and Internet of things (IoT) applications. DT frameworks, characteristic components, key technologies and specific applications are extracted for each DT category in this paper. A comprehensive survey of the DT references reveals the following findings: (1) The majority of existing DT models only involve one-way data transfer from physical entities to virtual models and (2) There is a lack of consideration of the environmental coupling, which results in the inaccurate representation of the virtual components in existing DT models. Thus, this paper highlights the role of environmental factor in DT enabling technologies and in categorized engineering applications. In addition, the review discusses the key challenges and provides future work for constructing DTs of complex engineering systems.

EXPERIMENTAL, engineering may be considered as the cornerstone of the aeronautical industry, regardless of the fact that the very nature of the work involved often calls for large expenditures without prospect of immediate return. Unlike engineering, the sales of a new model are not answerable to any known formulæ, making it necessary to consider that all capital invested in an experimental project may be lost, unless sales sufficient to defray all development costs are realized.

AT last there is conclusive evidence, of that which we have hitherto proclaimed namely, that incentive schemes based on time and motion study are the best and most satisfactory means, to worker and management alike, of increasing productivity.

This paper reconsiders the criticisms of the most influential theory of the rise of the large corporations, and to see how these criticisms can be met without entirely abandoning the basic elements of the theory.

This problem is approached by first analyzing the weaknesses inherent in Chandler's theory as presented in The Visible Hand, and then by reworking elements of the theory by relying on data generated by other historical accounts.

The author found that the theory could be salvaged by reordering the evolution of managerial practices based on a variety of historical studies, many not considered by Chandler, but even some of his own earlier work. Given these changes in historical order, vital managerial reforms can be placed sufficiently early that organizational techniques existed to solve the problems and exploit the opportunities that Chandler identifies as creating the pressures necessary to generate the large industrial corporation, thus responding to one class of criticism. My approach can also incorporate other factors that critics see as missing in Chandler's account.

What is new in this paper is that it reconciles Chandler's analysis with those of his critics by re‐examining and correcting some of his assumptions. The result is a theory of corporate evolution that is less global but more realistic. Economic and business historians as well as sociologists of organizations will find this reassessment valuable.

Time standards are essential to plan and analyze manufacturing processes. A key element of process planning that is not generated from a typical computer‐aided process plan (CAPP) is the process time standards. Generative process planning that includes time standards is particularly needed in the construction steel building (CSB) industry due to variability in projects (orders) size and content. Hence, the purpose of this paper is to focus on incorporating time standards into CAPP of CSB.

Empirical formulas are developed to generate time standards for variant steel beams based on their CAD files (design parameters and geometry) and process parameters (operational conditions). A Motion and Time Study (MTS) is used to estimate times for manual work elements such as load/unload activities and to validate the generated time standards. A generic parametric model is developed with Excel and integrated into the CAPP system to automatically estimate the standard time of each process operation.

Results showed that developing the time standards module for process operations and integrating its spreadsheets into a generative CAPP has helped process planners to arrive at better estimates of process parameters and has helped production management and the overall project management process in CSB industry.

The application of the proposed approach is not limited to CSB industry but it can also contribute to the continuing growth of CAPP applications in other industries.

The study is unique since it incorporates time standards into the architecture of CAPP system for accurate time and cost estimation and effective resource allocation and project management and it utilizes motion and time study (MTS) to collect complementary process data and validate the model‐generated cycle times.

Subtractive manufacturing process is the controlled removal of unwanted material from the parent workpiece for having the desired shape and size of the product. Several types of available machine tools are utilized to carry out this manufacturing operation. Selection of the most appropriate machine tool is thus one of the most crucial factors in deciding the success of a manufacturing organization. Ill-suited machine tool may often lead to reduced productivity, flexibility, precision and poor responsiveness. Choosing the best suited machine tool for a specific machining operation becomes more complex, as the process engineers have to consider a diverse range of available alternatives based on a set of conflicting criteria. The paper aims to discuss these issues.

Case-based reasoning (CBR), an amalgamated domain of artificial intelligence and human cognitive process, has already been proven to be an effective tool for ill-defined and unstructured problems. It imitates human reasoning process, using specific knowledge accumulated from the previously encountered situations to solve new problems. This paper elucidates development and application of a CBR system for machine tool selection while fulfilling varying user defined requirements. Here, based on some specified process characteristic values, past similar cases are retrieved and reused to solve a current machine tool selection problem.

A software prototype is also developed in Visual BASIC 6.0 and three real time examples are illustrated to validate the application potentiality of CBR system for the said purpose.

The developed CBR system for machine tool selection retrieves a set of similar cases and selects the best matched case nearest to the given query set. It can successfully provide a reasonable solution to a given machine tool selection problem where there is a paucity of expert knowledge. It can also guide the process engineers in setting various parametric combinations for achieving maximum machining performance from the selected machine tool, although fine-tuning of those settings may often be required.

This research aims to develop a new generic framework for estimating different maintenance costs (preventive, corrective and conditional based) and its distribution to original equipment manufacturer (OEM), customer and supply chain due to no fault found (NFF) events. The study extend the domain of NFF to military aircraft maintenance, repair and overhaul (MRO) by including broader range of cost drivers than are normally found in maintenance NFF literature.

The research applies the soft system methodology involving 80 field surveys and five in depth semi-structured interviews with practicing experts having background in military aircraft NFF MRO. For impact analysis, authors have used an agent-based model to represent and prioritize the critical NFF cost drivers during aircraft MRO based on the cost inputs of 21 technology transfer cases.

The paper provides imperial insights about how NFF cost drivers affect the OEM, customer and supply chain. It suggests that NFF cost need to be part of the commercial MRO contract, depending on its frequency pattern in different types of maintenances.

The context of the current research is military aircrafts industry and may lack generalizability to commercial aircrafts. Therefore, researchers are encouraged to test the proposed propositions further.

The developed framework will provide invaluable help in key financial decision-making during signing of MRO contract in technology transfer cases.

This paper proposed a new prediction model for NFF cost estimation across its shareholders and current status of NFF in military aircraft NFF MRO in India.

The purpose of this paper is to outline the skills and responsibilities of a careers master in the late 1950s.

Schools were becoming more businesslike, and training was becoming more specialised and developed. Schools needed to have an “Officer of Information” or a “Careers Master” in order to make sure that students had the appropriate qualifications in order to follow a career path with a particular firm. The author suggests that schools needed to do more for the students than simply provide an encyclopaedia of different occupations. This paper lists the practical steps a careers master needed to take, in terms of useful literature, notices and advertisements and also in terms of giving vocational guidance to students.

This article outlines the main responsibilities of a careers master and details some of the methods he/she should be able to use.

This paper suggests ways in which the role of a careers master in schools can aid students to gain the appropriate qualifications and to gain further information regarding potential future careers.