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The strain energy method for the analysis of pin‐jointed redundant frameworks is expressed in matrix form suitable for solution on electronic computers. This is illustrated by its application to a zero‐length launcher framework having sixty‐three members, nine of which are redundant, using the Ferranti Pegasus computer. It is concluded that a framework must be reasonably complex before the use of this method is justified but that problems of greater complexity than would normally be attempted can readily be solved.

The purpose of this paper is to describe how a discrete element model is used to predict the penetration depth and the perforation caused by a non‐deformable missile against a thin reinforced concrete slab.

Initial calibration of the model was done with a series of flat‐nose missile tests. Additional simulations were performed with varying the percentage of reinforcement. The present numerical model is compared to experimental test data provided by the French Atomic Energy Agency (CEA) and the French Electrical Power Company (EDF).

For thin concrete slabs, the evolution of the penetration depth in terms of percentage of reinforcement was compared with experimental results: quantitatively the results are very coherent.

The modeling scale is higher than the heterogeneity scale, so the model may be used to simulate real structures, which means that the discrete element method is mainly used here for its ability to account for discontinuities; an identification process based on quasi‐static tests is used, so the quasi‐static behavior of concrete is reproduced. This identification process is the key point, to allow a complete predictive computation for complex impact configurations, especially when the missile diameter and the thickness of the concrete slab are on the same order in size.

The orientation of a rigid body is described by a position‐tensor, composed of three unit vector axes fixed in the body; rotation is effected by tensor transformations in which a rotational operator is a Cartesian matrix, formed from the co‐ordinates of the pivot axis and components of the angle of rotation; rotational sequences are represented by matrix products. Three practical applications are discussed: sequences of aircraft manoeuvres, which include composite rotations of roll and pitch, or roll, pitch and yaw, applied simultaneously; the variation of sweep, incidence and dihedral of a wing moving on any axis fixed in the aircraft; the direction of the pivot axis and the angle of rotation in the motion of a retractable undercarriage between two specified positions.

The purpose of this paper is to identify the key facilitating factors for smart sustainable practices (SSP) and develop a project evaluation model (PEM) for SSP implementation in Nigeria and Hong Kong. SSP is coined from the integration of digital technologies such as Building Information Modelling (BIM) to facilitate sustainability practices.

The study employed a quantitative research design approach using empirical questionnaire surveys to solicit the opinions of 69 and 97 construction practitioners in Nigeria and Hong Kong. Purposive and snowball sampling techniques were used to identify the potential survey respondents. The fuzzy synthetic evaluation technique was used to develop the PEMs.

The findings revealed that adequate technical expertise of the SSP processes is critical in enhancing its implementation in Hong Kong and Nigeria; as well as the provision of training programs for specialists in smart and sustainable initiatives. Meanwhile, the study's findings advocated that for an SSP-enabled construction project, its project performance is mainly influenced by the client's satisfaction level and the early involvement of the project teams.

The study's results are limited to the Nigeria and Hong Kong construction industries.

Construction stakeholders such as the clients, developers, contractors can utilize the PEMs to determine and track SSP initiatives implementation in building projects in a reliable and practical way.

No tool has been developed for evaluating SSP initiatives at the project level in the construction industry. Using case studies of Hong Kong and Nigeria, PEM indices were developed to measure and track SSP implementation in construction projects.

The optimal design of a laminated cylindrical shell is obtained with the objectives defined as the maximisation of the axial and torsional buckling loads. The ply angle is taken as the design variable. The symbolic computational software package MATHEMATICA is used in the implementation and solution of the problem. This approach simplifies the computational procedure as well as the implementation of the analysis/optimisation routine. Results are given illustrating the dependence of the optimal fiber angle on the cylinder length and radius. It is shown that a general purpose computer algebra system like MATHEMATICA is well suited to solve small boundary value problems such as structural design optimisation involving composite materials.

The purpose of this paper is to investigate the effects of dipentaerythritol hexaacrylate (DPHA) and 3-(trimethoxysilyl)propyl methacrylate-modified silica nanoparticles (MSiO₂) contents on the performances of the Disperse Red 1 (DR1)-grafted-silica/poly(acrylate) color hard coatings.

The organic dye DR1 was silylated by reaction with the coupling agent 3-isocyanatopropyltriethoxysilane in methyl ethyl ketone. The silylated-DR1 thus obtained was grafted on MSiO₂ to form dye-grafted silica (GSiO₂). This hybrid dye was then UV-cured with the cross-linking agent, DPHA, to yield color coatings. Thermal durability of the coatings was evaluated based on their CIE (international commission on illumination) chromaticity coordinates and UV/Vis transmittances.

The results indicated that GSiO₂-coatings could tolerate thermal attack better than pristine DR1-coatings or dye-absorbed silica (DSiO₂)-coatings because of the fact that DR1 was more finely dispersed in the polymer binder when covalently bonded to the silica particles. Under optimal conditions, coatings with very small change of saturation and hue after high-temperature treatments were obtainable. These coatings appeared transparent, had 3H-6H pencil hardness and adhered perfectly onto the poly(methyl methacrylate) substrates.

Dye-grafted color coatings may find applications such as color filter photoresists for displays, microelectronics, printed circuit boards, etc.

The performances of the coatings were evaluated in terms of mechanical strength, adherence to the substrate, transmittance and color stability against heat treatments, which have not been disclosed. Also, using a newly developed triangular composition diagram, suitable ranges for preparing useful color coatings were accessed. The present method deserves further research studies on green and blue dyes.

THE orthodox solution of Lagrangian frequency equations involves the expansion into polynomial form of the characteristic determinantal equation in the latent roots, but this method becomes exceedingly laborious if a large number of frequencies and their associated modes are required accurately for any system of equations of high order, say above the sixth. We define a system of Lagrangian frequency equations to be of the nth order if it consists of n equations for n homogeneous unknowns, which we call modes. A useful contribution to the problem was made by the iteration solution of Duncan and Collar, which is especially valuable when only the highest one or two latent roots are required. But when an aircraft propeller vibration problem required the first seven frequencies and their associated modes for a 12th‐order equation whose coefficients involved a variable pitch angle, the labour of calculation by this method appeared at that time (1941) to be prohibitive. The ‘Escalator’ method was therefore devised jointly by the author and Captain J. Morris of the Royal Aircraft Establishment as an alternative. In the propeller problem all the latent roots involved were necessarily real. Dr L. Fox, using relaxation methods, has recently solved a similar problem in a remarkably short time. Unfortunately, relaxation methods cannot easily be extended to the case of complex latent roots, which can occur in connexion with flutter, radio circuits and other problems. In this paper it is shown how the Escalator method can be adapted without essential change to cases in which complex quantities occur.

This paper seeks to explore the applicability and implications of Bourdieu's field‐capital theory for marketing using original research with a typical European society. Bourdieu's field‐capital theory proposes that people acquire economic, social and cultural capital which they deploy in social arenas known as “fields” in order to compete for positions of distinction and status. This exploratory study aims to examine how Bourdieu's theory may explain competitive behavior in fields of interest to marketers.

A total of 61 in‐depth interviews were completed with respondents that were representative of each of 61 geodemographic “types” – clusters that enable marketers to segment an entire population.

The findings suggest that examining human behaviour through the lens of field and capital theory highlights the importance of the competition motive in explaining consumers' behaviour. New “fields” were identified which seem to have assumed primary importance, particularly in middle‐class people's lives.

Viewing consumer behaviour as social competition implies that new segmentation approaches may yield successful marketing outcomes, and opens consumer psychology and behaviour itself to new interpretations.

Very few research papers that apply field‐capital theory to marketing are present in the literature. It is hoped that this work addresses an important area, and one that is particularly prevalent in twenty‐first century consumerism.

The purpose of this study was to investigate the factors impacting the intermediating variable of employee engagement toward employee performance in a hybrid working organization in Bangkok, Thailand.

This study uses secondary data analysis and an archival study; the primary data were gathered from 370 employees who are working in a hybrid model environment in a private agricultural machinery company. To construct a new conceptual framework, this study adopted four frameworks from the previous research.

Perceived organizational support and trust and respect in the organization are found to have a significant positive impact on employee engagement. Moreover, there is a significant positive impact of the employee engagement on employee performance in a hybrid working model.

For hybrid work environments, the research focused mainly on the emotional themes of perceived support, trust and respect in the organization. Therefore, there would be many factors that could possibly affect those dependence variables in any environment, which will have to be investigated more in future research. Either in the organization or in the company, many departments and business units operates for the company, but the researcher specifies only the business units or departments that now use the hybrid working model.

This study focuses on a case study of an agricultural machinery company, which likely produces different results than other industries, other industries may produce different results.

Hybrid working models can blur the boundaries between work and personal life, potentially leading to increased stress and burnout. Organizations should prioritize work-life balance and employee well-being by promoting flexible schedules, encouraging breaks and time off, and providing resources for mental health support.

The organization which is operating among a hybrid working model, the increasing of perceived organizational support and trust and respect level, has positively increase the employee engagement toward enhancing the employee performance.

In the light of high reliance on digital technology to mitigate the consequences of the coronavirus disease 2019 (COVID-19) pandemic and its containment measures, this study investigates the factors influencing firms' decision to adopt digital technologies during COVID-19 in four Middle East and Northern African (MENA) countries, namely, Egypt, Jordan, Morocco and Tunisia.

The study used the International Labour Organization (ILO)/Economic Research Forum (ERF) COVID-19 - MENA Monitor Enterprise Survey (CMMENT), comprising 5,480 firms, surveyed during 2020–2021. The empirical model is estimated using the linear probability model (LPM) to address the problem of unobserved heterogeneity between firms, countries, and time.

The results revealed that firm characteristics, such as firm size and foreign ownership, encourage digital transformation in the business sector. Moreover, firms that face challenges during the pandemic, comply with the containment measures, and receive government assistance are more likely to adopt digital solutions. Furthermore, the results indicated that firms operating in services sector have a higher likelihood to adopt digital technology. Disaggregating the total sample into several sub-samples, the results are robust across countries and technology types, supporting the initial hypothesis that COVID-19 encourages digital transformation in the MENA region.

The study has numerous contributions. First, to the best of the authors' knowledge, this is the sole study that uses micro data collected during the COVID-19 to examine the factors influencing firms' decision to adopt and invest in digital solutions in the MENA countries. Second, the paper employs the LPM estimator to address the issue of unobserved heterogeneity between firms, countries and time. Finally, the paper offers some practical recommendations for accelerating digital transformation in MENA region.