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Climate change is a vortical situation of increasing turbulent conditions called the “sixth extinction.” In this chapter I begin with the two-dimensional Archimedean spiral (the coiling rope), move on to the three-dimensional corkscrew spiral (or threaded screw), and on to the three-dimensional double spiral of upward and descending movement with many nested vortices. The latter is more necessary to understand climate change, and our possible future in it, than the flat spirals. Ironically, Plato wrote about the double-twisted spiral with its nested vortices long ago. We are in a double-spiralic helice, a vortical phenomenon with centripetal and centrifugal, upward-ascending and downward-descending waves, and left and right turning whorls. It is worse than this. We need to challenge spiral symmetry thinking. There is no reality axis around which the spiralic helice is spinning, and there is no symmetry. There is no uniformity to the spiralic vortices of turbulence of the sixth extinction.

This research aims to examine the ways and the extent to which social media platforms undermine the spiral of silence by facilitating the expression of diverse voices and opinions.

Semi-structured interviews were conducted with members of closed groups focused on non-consensus topics.

Facebook closed group members perceive the media as isolating and portraying their issues negatively. However, these groups offer support, inclusion and non-judgmental opinion-sharing space. Consequently, members feel more comfortable discussing and sharing the topic outside the group, indicating a slight trend of challenging and undermining the spiral of silence through social networks.

The study faces challenges in comparing diverse groups due to unique circumstances, complex needs and societal attitudes. Each group stands alone, potentially yielding slightly different findings.

Social media challenges and undermines the spiral of silence, as these opinions are shared with the wider society and can even find their way back to mainstream media outlets. Thus, social media platforms play a significant role in disrupting the spiral of silence and facilitating the expression of diverse opinions that may have been previously suppressed.

This research emphasizes the critical role of social media in shaping public opinion and its interaction with the broader media landscape, illustrating a circular process where social media disrupts the spiral of silence by facilitating the expression of previously suppressed diverse opinions, which can then potentially influence mainstream media.

This study adds value by exploring how social media platforms can challenge and undermine the spiral of silence, enabling the expression of diverse, marginalized and underrepresented opinions in society. It highlights the role of social media in shaping public opinion and discourse, challenging the dominance of traditional media. Its originality emanates from its revelations concerning the legitimization of conversational topics, which may consequently affect media agendas.

This study aims to investigate the effects of using circular spirals as the longitudinal reinforcing bars on the performance of the concrete beams subjected to four-point bending load.

The effects of using circular spirals as the longitudinal reinforcing bars on the performance of the concrete beams subjected to four-point bending load are investigated in this study. Employing circular spirals as the main longitudinal reinforcement is a novel idea presented in this paper. In this regard, a finite element model of the beam with spiral longitudinal reinforcement was developed. After model verification, several configurations of concrete beams reinforced by longitudinal spirals were simulated under the four-point loading condition.

Obtained results showed that using the longitudinal spirals in place of the conventional longitudinal reinforcing bars can improve the bearing capacity of the concrete beam, but at the same time, increases its ductility unacceptably. In other words, the spirals reduce the initial stiffness of the beam significantly. To solve the problem, the authors decided to use the longitudinal spirals as the auxiliary bars added to the main conventional longitudinal bars in the beams. New gained results were satisfactory. By adding the longitudinal spirals to the conventional bars, not only the bearing capacity of the beam increases between 24% and 63%, but also the initial stiffness and ductility of the beam raises between 11%–29% and 3%–57%, respectively, in comparison to the corresponding beam reinforced with conventional longitudinal bars.

Employing circular spirals as the main longitudinal reinforcement is a novel idea presented in this paper.

The purpose of this paper is to introduce the development of a knowledge management system. It allows the creation of new knowledge, its consolidation, distribution and combination in the field of educational innovation, in such a way that the knowledge is transferred from individuals to the organisation and from the organisation to individuals. To achieve this, the knowledge spirals of Nonaka are integrated. The epistemological spiral is used to obtain the ontologies that feed the ontological spiral.

More than 600 university teachers participated in the research and the development of the management system, in which more than 400 educational innovation experiences and 1,100 authors have been included.

The epistemological spiral is used to obtain the ontologies that feed the ontological spiral. The result is a double spiral that allows the contribution of a conceptual model and the development of an innovative tool that enables and automates the effective management of knowledge in educational innovation.

A repository about educational innovation best practices and experiences is available.

The presented model for the sustainability and evolution for an educational innovation best practices repositories has a huge impact for education innovation recognition in the professional development of university teachers. On the other hand, it is way of sharing best practices of educational innovation all over the world.

The major contribution of this research work is based on the way that the knowledge is transferred from individuals to the organisation and from the organisation to individuals. The classification schema and the proposed indicators are based on the elicitation of more than 600 experts and the study of a corpus of more than 400 educational innovation experiences that involve 1,100 university teachers approximately.

Instantaneous radial force induced from unsteady flow will intensify vibration noise of the centrifugal pump, especially under off-design working conditions, which will affect safety reliability of pump operation in severe cases. This paper aims to conduct unsteady numerical computation on one centrifugal pump; thus, unsteady fluid radial force upon the impeller and volute is obtained, so as to study the evolution law of instantaneous radial force, the internal relationship between radial force and pressure pulsation, the relationship among each composition of radial force that the impeller received and the influence of leakage rate of front and back chamber on radial force.

The unsteady numerical simulation with SST k-ω turbulence model was carried out for a low specific-speed centrifugal pump using computational fluid dynamics codes FLUENT. The performance tests and pressure tests were conducted by a closed loop system. The performance curves and the pressure distribution from numerical simulation agree with that of the experiment conducted. The unsteady pressure distributions and the instantaneous radial forces induced from unsteady flow were analyzed under different flow rates. Contribution degrees of three components of the radial force on the impeller and the relation between the radial force and leakage rate were analyzed.

Radial force on the volute and pressure pulsation on the volute wall have the same distribution tendency, but in contrast to the distribution trend of the radial force on the impeller. In the component of radial force that the impeller received, radial force on the blade accounts for the main position. With the decrease of flow rate, ratio of the radial force on front and back casings will be increased; under large flow rate, vortex and flow blockage at volute section will enhance the pressure and radial force fluctuation greatly, and the pulsation degree may be much more intense than that of a smaller flow rate.

This paper revealed the relation of the radial force and the pressure pulsation. Meanwhile, contribution degrees of three components of the radial force on the impeller under different working conditions as well as the relation between the radial force and leakage rate of front and rear chambers were analyzed.

The purpose of this paper is to develop a new model for depicting organizational processes: the episodic spiral model (ESM).

On the basis of a strong process view as the orienting paradigm, the authors demonstrate the need for the ESM by discussing the shortcomings of two specific spiral types in the organizational literature – the knowledge creation spiral and the efficacy spiral.

A review of each spiral type through the lens of nonlinear assumptions reveals the treatment to date of organizational spirals as uni-directional and insufficient for understanding organizations. The authors propose that managers must undertake a paradigm shift in order to gain a greater awareness of both the environment in which they operate, as well as their process actions. To facilitate this shift, the ESM depicts choice points, chosen and rejected trajectories, and upward and downward environmental drafts, as well as a multi-dimensional environment, as a way of re-conceptualizing approaches to space, time, and change in organization studies.

The authors propose that the model provides a way for scholars to enhance the study of organizations by understanding that organizations exist in a more dynamic environment than previously studied; recognizing that the organization has a wider range of choices available, and acknowledging the long-lasting ramifications of both choices made and choices discarded; and obtaining a more comprehensive look at the way the organization moves through space and time at any given moment. Taken together, the authors hope that these contributions allow organizational scholars a new approach to theorizing, exploring, and writing about the organizations they study.

The purpose of this paper is to analyse how different strengths of simmelian ties affect knowledge spirals and investigate which major factors affect the influence of simmelian ties on knowledge spirals.

The empirical data in this paper were collected through e-mail and interview questionnaires to R&D teams in high-tech manufacturing enterprises in China. The authors obtained 132 teams' valid responses. The interval decision-making trial and evaluation laboratory (interval DEMATEL) method, differential evolution (DE) algorithm and Bayesian structural equation modelling (BSEM) were employed to test the theoretical framework developed for this paper.

The results show that strong simmelian ties have positive associations with high-performance work practices (HPWPs). Meanwhile, weak simmelian ties have positive associations with HPWPs. Furthermore, HPWPs and knowledge fermentation play a conducive role in the relationship between simmelian ties and knowledge spirals.

This paper contributes in three ways. First, it extends research on the relational antecedents of knowledge spirals. Second, this paper extends the study of social capital related to knowledge spirals. Third, this paper elucidates less familiar factors relating HPWPs to knowledge fermentation by testing the mediating role of HPWPs in knowledge fermentation.

This study aims to study the gas film stiffness of the spiral groove dry gas seal.

The present study represents the first attempt to calculate gas film stiffness in consideration of the slipping effect by using the new test technology for dry gas seals. First, a theoretical model of modified generalized Reynolds equation is derived with slipping effect of a micro gap for spiral groove gas seal. Second, the test technology examines micro-scale gas film vibration and stationary ring vibration to determine gas film stiffness by establishing a dynamic test system.

An optimum value of the spiral angle and groove depth for improved gas film stiffness is clearly seen: the spiral angle is 1.34 rad (76.8º) and the groove depth is 1 × 10^–5 m. Moreover, it can be observed that optimal structural parameters can obtain higher gas film stiffness in the experiment. The average error between experiment and theory is less than 20%.

The present study represents the first attempt to calculate gas film stiffness in consideration of the slipping effect by using the new test technology for dry gas seals.

The purpose of this study is to design and develop new spiral head projectiles undergoing ballistics impact.

The introduction of the rifled barrel in firearms made projectile spin during its flight path. The central translational velocity (impact velocity) is one parameter to defeat/penetrate the target in the penetration process. Another important parameter considered to be the shape of the projectile. Many types of projectile shapes have been designed to defeat the target. In the recent years, ogival nose shape is one of the well-known projectile shapes in use abundantly. The present research is made to design the nose shape so as to use the spin during the penetration of target effectively. In this study, a new spiral head projectile shape is proposed and designed, which uses the rotation of projectile (spin) for penetrating the Al7075-T6 target. When the ogive and new spiral head projectile is impacted on Al 7075-T6 target of 12.5 mm, 18 mm thicknesses at ordnance velocities, the residual velocity is evaluated numerically using ANSYS/Explicit Dynamics at normal impact condition. Two projectile materials, steel 4340 and tungsten alloy, are used as projectile materials. Along with the translational velocity, rotation velocities (spin rate) 13,000, 26,000 and 52,000 rad/s also provided to projectile. The residual velocities verses spin rate are plotted for different spiral angle projectiles for impact velocities 1,000–1,500 m/s, at normal impact conditions on the Al 7075-T6 target. Compared with the ogive nose projectile, the proposed new spiral head projectile made of tungsten alloy is significantly effective.

Spiral head projectile having tungsten alloy material gives encouraging results at 12.5 mm target thickness. The new spiral head projectile is damaged partially. At 18 mm target thickness impact conditions, it is observed that the projectile head is completely damaged. The effectiveness of spiral head projectile on a target plate thickness of 18 mm is considered to study the impact condition.

All the above results need to be experimentally verified. However, the basic numerical model used in the present study, i.e. the basic ogive nose numerical model with only translational energy, is well validated with penetration theory available in literatures.

The designed new spiral head projectile is only effective with tungsten alloy material within considered design parameters. For steel 4340 material, the spiral head projectile is less effective than the ogive nose projectile. In tungsten alloy projectiles, by observing all considered spiral angles, 30-degree spiral angle projectile gives the best performance at most of the considered impact velocity conditions.

The proposed research outputs are original, innovative and, have lot of importance in defence applications particularly in arms and ammunitions.

Knowledge input development and innovation implementation are new features of industrial technology innovation. The purpose of this study is to find the process of coordination and ecological spiral in the ambidextrous innovation of industrial technology.

To design the model of industrial technology ambidextrous innovation based on knowledge ecology spiral, an input-output model of knowledge for ambidextrous innovation and a spiral model of knowledge ecology were constructed based on an improved Lotka-Volterra model. Then, the equilibriums in different knowledge inputs and the spiral evolution of knowledge ecology were analyzed. Finally, the ambidextrous coordination mechanism of the core organization was revealed.

By coordinating the knowledge inputs and the knowledge ecology spiral, enterprises extend the R&D investments in the innovation chain, which will facilitate the knowledge inputs of the exploitative and exploratory innovation. Implementing the ambidextrous coordination in the technology innovation chain and the knowledge ecology chain has the advantage of promoting knowledge inputs, mobility and ecological spiral. Meanwhile, it can achieve the “multi-source, integration and coordination” development of industrial technology innovation.

The two-element innovative knowledge input coordination model and the knowledge ecological spiral model based on the improved Lotka-Volterra model are constructed, which extends the modeling way of the traditional knowledge input-output profit model. It is expected to reduce the amount of knowledge input of a single member and provide theoretical reference for improving the efficiency of knowledge input by constructing the inter-dependent regenerative and inter-generative knowledge interaction.