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This paper aims to inform the discussion on why and how non-profit organizations can experience a hybridization process to address the criticism that would assume hybridity as an intrinsic characteristic of all organizations. Specifically, by referring to the academies of intellectuals as the non-profit setting in which investigating the emergence of hybridity takes place, this paper aims at exploring, first, to what extent this emergence could be induced by institutional conditions, and, second, which structural innovations could sustain the academies’ “motion” towards hybridity.

This paper relies on the institutional logics perspective and adopts the case study method applied to a historical context. The case under analysis is the Academy of “the Immobili”, which, in spite of its name, experienced a hybridization process in 1720 because of the decision to involve an impresario in the management of its theatre.

The findings highlight the significant role played by institutional conditions in inducing the emergence of hybridity, even in presence of internal resistance to any “motion” from the non-profit setting. Moreover, the analysis of the innovations associated with this emergence detects the intertwined action of the different decision makers involved in the hybridization process, in spite of their formal separation. These findings strengthen the conceptualization of hybridity within non-profit organizations.

Besides referring to a historical period that is still little explored in terms of hybridity within organizations, the paper focuses on an original context, i.e. academies, representing an ancient typology of cultural organizations. Therefore, the paper also provides the first insights into the hybridization process of cultural organizations from a historical perspective.

Tandem wing aircrafts belong to an unconventional configurations group, and this type of design is characterised by a strong aerodynamic coupling, which results in lower induced drag. The purpose of this paper is to determine whether a certain trend in the wingspan impact on aircraft dynamic stability can be identified. The secondary goal was to compare the response to control of flaps placed on a front and rear wing.

The aerodynamic data and control derivatives were obtained from the computational fluid dynamics computations performed by the MGAERO software. The equations of aircraft longitudinal motion in a state space form were used. The equations were built based on the aerodynamic coefficients, stability and control derivatives. The analysis of the dynamic stability was done in the MATLAB by solving the eigenvalue problem. The response to control was computed by the step response method using MATLAB.

The results of this study showed that because of a strong aerodynamic coupling, a nonlinear relation between the wing size and aircraft dynamic stability proprieties was observed. In the case of the flap deflection, stronger oscillation was observed for the front flap.

Results of dynamic stability of aircraft in the tandem wing configuration can be found in the literature, but those studies show outcomes of a single configuration, while this paper presents a comprehensive investigation into the impact of wingspan on aircraft dynamic stability. The results reveal that because of a strong aerodynamic coupling, the relation between the span factor and dynamic stability is nonlinear. Also, it has been demonstrated that the configuration of two wings with the same span is not the optimal one from the aerodynamic point of view.

The very criticism of public policy being rigid and generalized on one hand, and insouciant and noncustomizable on the other has to be addressed to cope up with the comingled economic, social and environmental challenges. Policies that fail the litmus test of changing and challenging conditions will run the risk of not achieving their purpose and obstructing the ability of citizens, communities and businesses. This paper draws the case of Bangladesh to explore the principles of adaptive policies in the surfacing of the recently adopted Digital Commerce Management Guide 2021 under the National Digital Commerce Policy, 2020.

This is a qualitative paper that is based on both primary and secondary data. While secondary data on the policy crafted a strong call for increased adaptiveness, primary data extracted from the interviews presented several lacking and loopholes from respondents’ firsthand experiences. Based on secondary content and primary data from consumers and business owners of the most-used social commerce platform (a form of digital commerce), Facebook commerce, hereto referred to as F-commerce, this paper discusses the possible characteristics of adaptive policy-making for more innovative, contextual, gender-inclusive, efficient and environmentally sustainable policies.

The paper points out some reform and adjustment scope for the recently introduced digital commerce policy to make it more adaptive to the present and upcoming policy context.

It must be mentioned that there is a dearth of research on digital commerce policy and the platform as a whole.

Hence, this paper offers a fresh perspective toward time befitting policy formulation in the digital commerce sector and set in motion the policy attention that this platform requires.

This study aims to propose a vertical coupling dynamic analysis method of vehicle–track–substructure based on forced vibration and use this method to analyze the influence on the dynamic response of track and vehicle caused by local fastener failure.

The track and substructure are decomposed into the rail subsystem and substructure subsystem, in which the rail subsystem is composed of two layers of nodes corresponding to the upper rail and the lower fastener. The rail is treated as a continuous beam with elastic discrete point supports, and spring-damping elements are used to simulate the constraints between rail and fastener. Forced displacement and forced velocity are used to deal with the effect of the substructure on the rail system, while the external load is used to deal with the reverse effect. The fastener failure is simulated with the methods that cancel the forced vibration transmission, namely take no account of the substructure–rail interaction at that position.

The dynamic characteristics of the infrastructure with local diseases can be accurately calculated by using the proposed method. Local fastener failure will slightly affect the vibration of substructure and carbody, but it will significantly intensify the vibration response between wheel and rail. The maximum vertical displacement and the maximum vertical vibration acceleration of rail is 2.94 times and 2.97 times the normal value, respectively, under the train speed of 350 km·h⁻¹. At the same time, the maximum wheel–rail force and wheel load reduction rate increase by 22.0 and 50.2%, respectively, from the normal value.

This method can better reveal the local vibration conditions of the rail and easily simulate the influence of various defects on the dynamic response of the coupling system.

This paper evaluates the implementation of a school-based physical activity intervention and discusses how the intervention outcomes can be influenced by the implementation.

In four of the nine lower secondary schools in which the intervention was conducted, the authors examined implementation fidelity, adaptation, quality, responsiveness and dose received. The authors conducted focus group interviews with teachers (n = 8) and students (n = 46) and made observations. Dose delivered was examined quantitatively, with weekly registrations.

Results showed that two out of four schools made few and positive adaptations, implemented the intervention with high fidelity and quality and responded positively. Four main factors were found to influence implementation: frame factors, intervention characteristics, participant characteristics and provider characteristics.

A cross-sectional design was used and may not represent implementation throughout the whole school year.

In terms of large-scale implementation, the intervention may be generalizable. However, intervention criteria such as adequate facilities and a flexible timetable may be unattainable for some schools. The intervention can be adapted without compromising its purpose, but adaptations should be a result of cooperation between students and teachers.

Process evaluations on this topic are rare. This study adds to a limited knowledge base concerning what factors may influence implementation of school-based physical activity interventions for adolescents.

The purpose of this study is to introduce the top-level design ideas and the overall architecture of earthquake early-warning system for high speed railways in China, which is based on P-wave earthquake early-warning and multiple ways of rapid treatment.

The paper describes the key technologies that are involved in the development of the system, such as P-wave identification and earthquake early-warning, multi-source seismic information fusion and earthquake emergency treatment technologies. The paper also presents the test results of the system, which show that it has complete functions and its major performance indicators meet the design requirements.

The study demonstrates that the high speed railways earthquake early-warning system serves as an important technical tool for high speed railways to cope with the threat of earthquake to the operation safety. The key technical indicators of the system have excellent performance: The first report time of the P-wave is less than three seconds. From the first arrival of P-wave to the beginning of train braking, the total delay of onboard emergency treatment is 3.63 seconds under 95% probability. The average total delay for power failures triggered by substations is 3.3 seconds.

The paper provides a valuable reference for the research and development of earthquake early-warning system for high speed railways in other countries and regions. It also contributes to the earthquake prevention and disaster reduction efforts.

This paper aims to develop a credit-risk model in which firms face rollover risk, and the markets for defaulted assets are segmented due to entry costs. The paper shows that reducing the entry costs in this economy may decrease the total surplus of the economy. This outcome can arise because when market barriers are lifted, the gap between the liquidation prices across the markets will shrink, but then the market that would experience a price drop may face more bankruptcies because the rollover risk will increase in that market. The paper describes under which condition such an intervention policy improves or hurts the total surplus.

Female adults diagnosed with myalgia encephalomyelitis (ME) and chronic fatigue syndrome (CFS) often are marginalised because their condition is not fully recognised by medical and health-care systems. The purpose of this small-scale study was to explore the lived experiences of adult females with ME/CFS in England in relation to contributing factors that impact their occupational participation.

A qualitative study design using semi-structured interviews was used with nine female adult participants who were selected using a purposive sampling method. A Thematic Networks tool was used to analyse data.

Four organising themes were identified: impairment-, person-, environment- and society-related factors. Two global themes, invisibility and diagnosis stigma, were identified as the overarching issues that female adults with ME/CFS face in occupational participation.

Many of the issues that contribute to lack of participation by this population are associated with environmental factors which are secondary to their illness.

Accurately estimating the severity of derailment is a crucial step in quantifying train derailment consequences and, thereby, mitigating its impacts. The purpose of this paper is to propose a simplified approach aimed at addressing this research gap by developing a physics-informed 1-D model. The model is used to simulate train dynamics through a time-stepping algorithm, incorporating derailment data after the point of derailment.

In this study, a simplified approach is adopted that applies a 1-D kinematic analysis with data obtained from various derailments. These include the length and weight of the rail cars behind the point of derailment, the train braking effects, derailment blockage forces, the grade of the track and the train rolling and aerodynamic resistance. Since train braking/blockage effects and derailment blockage forces are not always available for historical or potential train derailment, it is also necessary to fit the historical data and find optimal parameters to estimate these two variables. Using these fitted parameters, a detailed comparison can be performed between the physics-informed 1-D model and previous statistical models to predict the derailment severity.

The results show that the proposed model outperforms the Truncated Geometric model (the latest statistical model used in prior research) in estimating derailment severity. The proposed model contributes to the understanding and prevention of train derailments and hazmat release consequences, offering improved accuracy for certain scenarios and train types

This paper presents a simplified physics-informed 1-D model, which could help understand the derailment mechanism and, thus, is expected to estimate train derailment severity more accurately for certain scenarios and train types compared with the latest statistical model. The performance of the braking response and the 1-D model is verified by comparing known ride-down profiles with estimated ones. This validation process ensures that both the braking response and the 1-D model accurately represent the expected behavior.

Despite the fact that there being a large literature on simulation, there is as yet no generic paradigm or architecture to develop a three-dimensional (3-D) simulator which depends on autonomous intelligent objects. This has motivated us to introduce a 3-D simulation system based on intelligent objects for Physics Experimentation. We formulated the system’s components as an object-orientation model. So, the entities in every experiment’s work cell are modeled by characterizing their properties and functions into classes and objects of the system hierarchy. Intelligent objects are realized by developing a knowledge base (KB) that captures a set of rules/algorithms that operate on 3-D objects. Rules fall into two categories: action and property rules. In the simulation layer, the student is allowed, by using the virtual system, to stroll throughout the Physics laboratory in light of a walking model. Student gets to a simulation region to do an experiment through the detection of mathematical collision. From software engineering perspective, the proposed system facilitates the Physics experiment through making the specification of its applicable parts more modular and reusable. Moreover, a major pedagogical objective is achieved by permitting the student tuning parameters, fixing component of a device then visualizing outputs. This provides student well interpretation by viewing how distinct parameters affect the outcomes of the experiment. With the objective of student performance measuring, we utilized an exploratory group relying upon pre- and post-testing. The application results demonstrate that the simulator contributes positively to student performance in regard to practical Physics.