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The purpose of this paper is to study the distribution of active earth pressure in retaining walls with narrow cohesion less backfill considering arching effects.

To this end, the approach of principal stresses rotation was used to consider the arching effects.

According to the presented formulation, the active soil pressure distribution is nonlinear with zero value at the wall base. The proposed formulation implies that by increasing the frictional forces at both sides of the backfill, the arching effect is increased and so, the lateral earth pressure on the retaining wall is decreased. Also, by narrowing the backfill space, the lateral earth pressure is extremely decreased.

A comprehensive analytical solution for the active earth pressure of narrow backfills is presented, such that the effects of the surcharge and the characteristics of the stable back surface are considered. The magnitude and height of the application of lateral active force are also derived.

The article examines the nature of pressure groups, their effect on corporate action and on managers. The importance of seeking an understanding of pressure groups is emphasised. Although pressure groups can be responsible for constraining corporate action, they can also sometimes present business opportunities.

This research aims to focus on developing a customized support surface using additive manufacturing (AM) for effective pressure relief for patients who are in bed or wheelchair suffering from pressure ulcers (PU).

A novel customized support surface is developed using AM technology incorporated with magnetic levitation and ball and socket mechanisms. Magnetic levitation provides cushioning effect for the developed cushion to users who are sitting in a wheelchair and increases the rate of healing. The ball and socket mechanism provides the user body's self-adaptive mechanism and reduces shear and friction forces between the surfaces of the additive manufactured cushion and the human buttocks.

From the results of ISO 16480-6 biomechanical standardized tests, the additive manufactured support surface performed better than, or on par with, the most widely available commercial cushions. It is evident that the developed cushion’s peak pressure values are lower when compared with other cushions. The overall efficiency of the developed cushion was qualitatively reported; 67% of people felt it was excellent and 22% of people responded as good and 11% were satisfactory. Henceforth, the overall effectiveness of the developed support surface provides a better experience to the end-user in the view of PU reduction.

A developed additive manufactured customized support surface will be an alternative approach for the reduction of PU, and it overcomes the drawbacks faced by the currently available cushions.

The purpose of this paper is establishing a general mathematical model and theoretical design rules for 3D printing of biomaterials. Additive manufacturing of biomaterials provides many opportunities for fabrication of complex tissue structures, which are difficult to fabricate by traditional manufacturing methods. Related problems and research tasks are raised by the study on biomaterials’ 3D printing. Most researchers are interested in the materials studies; however, the corresponded additive manufacturing machine is facing some technical problems in printing user-prepared biomaterials. New biomaterials have uncertainty in physical properties, such as viscosity and surface tension coefficient. Therefore, the 3D printing process requires lots of trials to achieve proper printing parameters, such as printing layer thickness, maximum printing line distance and printing nozzle’s feeding speed; otherwise, the desired computer-aided design (CAD) file will not be printed successfully in 3D printing.

Most additive manufacturing machine for user-prepared bio-material use pneumatic valve dispensers or extruder as printing nozzle, because the air pressure activated valve can print many different materials, which have a wide range of viscosity. We studied the structure inside the pneumatic valve dispenser in our 3D heterogeneous printing machine, and established mathematical models for 3D printing CAD structure and fluid behaviors inside the dispenser during printing process.

Based on theoretical modeling, we found that the bio-material’s viscosity, surface tension coefficient and pneumatic valve dispenser’s dispensing step time will affect the final structure directly. We verified our mathematical model by printing of two kinds of self-prepared biomaterials, and the results supported our modeling and theoretical calculation.

For a certain kinds of biomaterials, the mathematical model and design rules will have unique solutions to the functions and equations. Therefore, each biomaterial’s physical data should be collected and input to the model for specified solutions. However, for each user-made 3D printing machine, the core programming code can be modified to adjust the parameters, which follows our mathematical model and the related CAD design rules.

This study will provide a universal mathematical method to set up design rules for new user-prepared biomaterials in 3D printing of a CAD structure.

The purpose of this paper is to present a new approach of evaluation of the absorption line black body distribution function (ALBDF) for a mixture of gases. Currently published correlations, which are used to reproduce the ALBDF, treat only single gases.

A discrete form of the ALBDF is generated using line by line (LBL) calculations. The latest spectroscopic database HITEMP 2010 is used for the generation of the absorption coefficient histogram, which is cumulated later in order to produce a tabulated form of the ALBDF. The proper orthogonal decomposition (POD) statistical method is employed for the reproduction of the ALBDF. Interpolation property of the POD allows to reproduce the ALBDF for arbitrary gas mixture parameters.

POD proved to possess optimal interpolation properties. Results obtained by using POD are in very good agreement with LBL integration.

One have to be aware that the model generated with the POD method can be used only within the range of parameters used to build the model. The POD does not perform any property extrapolation. The model is limited to a mixture of two gases, namely CO₂ and H₂O. Expanding the number of gases used in the mixture may lead to a relatively large matrix system, which is difficult to process with the POD approach.

The presented approach can be used to produce absorption coefficients values and their weights, which can be applied in the gas radiative properties description using the weighted sum of gray gas (WSGG) concept. The proposed model can be used with any radiative transfer equation solver which employs the WSGG approach.

For the first time, radiative properties of gas mixtures are reproduced using the POD approach.

The purpose of this study is to find the optimum design of Reinforced Concrete (RC) pile foundation to enable efficient use of structural concrete with greater consequences for global environment and economy.

A non-linear optimisation technique based on the Generalised Reduced Gradient (GRG) algorithm was implemented to find the minimum cost of RC pile foundation in frictional soil. This was achieved by obtaining the optimum pile satisfying the serviceability and ultimate limit state requirements of BS 8004 and EC 7. The formulated structural optimisation procedure was applied to a case study project to assess the efficiency of the proposed design formulation.

The results prove that the GRG method in Excel solver is an active, fast, accurate and efficient computer programme to obtain optimum pile design. The application of the optimisation for the case study project shows up to 26% cost reduction compared to the conventional design.

The design and formulation of design constraints will be limited to provisions of BS 8004 and EC 7.

Since the minimum quantity of concrete was attained through optimisation, then minimum cement will be used and thus result in minimum CO₂ emission. Therefore, the optimum design of concrete structures is a vital solution to limit the damage to the Earth's climate and the physical environment resulting from high carbon emissions.

The current study considers the incorporation of different soil ground parameters in the optimisation process rather than assuming any pile capacity value for the optimisation process.

Despite blockchain's potential supply chain benefits, few organizations have moved beyond pilot projects. The paper aims to explore blockchain adoption intentions for supply chain applications using two theoretical perspectives: innovation diffusion theory (IDT) and institutional theory (IT).

Based on theory, five propositions were developed addressing the intention to adopt blockchain. The propositions were tested using scenario-based experiments with supply chain professionals. To provide additional insights, interviews with 21 supply chain professionals in 15 organizations representing 8 industries were content analyzed.

Experiments suggest that the intention to adopt blockchain is higher when there are government regulations regarding product origin, organizations are using updated cloud-based information systems and organizations are working with third-party consultants. The content analysis suggests that organizations that face normative pressures to adopt blockchain supply chain applications and recognize blockchain's relative advantage, compatibility and complexity are more likely to be actively seeking information about and adopting blockchain supply chain applications. The authors synthesize findings and provide new propositions to guide future research.

Using a multi-method approach, the study provides an important window into supply chain managers' perceptions of the necessary conditions to support organization-level blockchain adoption. The findings also indicate key characteristics present in supply chain networks poised for blockchain adoption.

Research in strategic human resource management (HRM) has focused mainly on the effects of HRM practices or systems on organizational effectiveness. However, institutional theory argues that besides being financially successful, organizations also need legitimacy to survive. Owing to the tension between competitive and institutional pressures, organizations balance between the degree of conformity and the degree of differentiation from competitors regarding HRM. The purpose of this paper is to address how institutional pressures help shape HRM.

Using the concepts of leeway, human agency and strategic choice, differences in three types of institutional fit are highlighted: innovative, conformist and deviant. A comparative case study approach is used in order to illustrate the framework, using document analysis and 43 interviews in three organizations in The Netherlands.

This paper shows how balancing competitive and institutional pressures in organizations affects HRM. The cases illustrate the proposed theoretical framework, showing leeway, human agency, strategic choice and the nature of institutional fit. The organizations each illustrate a type of institutional fit. Moreover, not the institutional context itself, but the organization's response seems to make a difference for the nature of institutional fit.

While previous studies focus on the effects of HRM on organizational effectiveness, this paper examines how the balance between competitive and institutional pressures affects HRM and aims to show that institutional fit can contribute to strategic HRM by providing insight in this more balanced goal setting of organizations.

This paper aims to present the results of an experimental investigation carried out to control the base pressure in a suddenly expanded axi‐symmetric passage.

Four micro‐jets of 1 mm orifice diameter located at 90° interval along a pitch circle diameter of 1.3 times the nozzle exit diameter in the base region was employed as active controls. The test Mach numbers were 1.25, 1.3, 1.48, 1.6, 1.8, 2.0, 2.5 and 3.0. The jets were expanded suddenly into an axi‐symmetric tube with cross‐sectional area 4.84 times that of nozzle exit area. The length‐to‐diameter ratio of the sudden expansion tube was varied from 10 to 1. Nozzles generating the above jet Mach numbers were operated with nozzle pressure ratio in the range 3‐11. As high as 40 per cent increase in base pressure was achieved. In addition to base pressure, the wall pressure in the duct was also measured.

It is found that the wall pressure is not adversely influenced by the micro jets.

The paper provides information on internal supersonic flow.

Purpose – This chapter presents the results of an exploratory study carried out on activist institutional investor strategies. It aims to identify the way in which different types of institutional investors are reacting to new institutional pressures in the French context.

Design/methodology/approach – Our methodology is based on a series of semi-directive interviews, combined with additional relevant data.

Findings – The interpretation of results makes use of institutional theory, more specifically the work of Oliver (1991). Our study shows that active institutional investors may opt for different responses when confronted with new institutional pressures, and that these responses would seem to depend on antecedents underlined by Ryan and Schneider (2002), which in turn depend on the nature of their business relationships with the firm in which they invest. Whereas pressure-sensitive investors (such as banks and insurance companies) generally adopt acquiescence responses, pressure-resistant investors (such as pension funds and investment funds) pursue joint strategies of co-optation, influence or control with key actors such as local and international proxy advisors and French investor associations. Acting conjointly, certain pressure-resistant investors are often considered as institutional entrepreneurs in that they initiate changes and actively participate in the implementation of new norms in the field of shareholder activism in the French context. In parallel to this ongoing professionalization, other pressure-resistant investors such as activist hedge funds seem to lack sufficient legitimate power to be effective.

Originality/value – This chapter illustrates that the level of institutional investor activism depends largely on the relevant national legal framework. It also shows how institutional investor coalitions take advantage of new institutional pressures to enhance their legitimacy or increase the effectiveness of their action.