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The purpose of this paper is to understand the effect of basin water depth towards the cumulative distillate yield of the traditional and developed single basin double slope solar still (DSSS).

Modified single basin DSSS integrated with solar operated vacuum fan and external water cooled condenser was fabricated using aluminium material. During sunny season, experimental investigations have been performed in both conventional and modified DSSS at a basin water depth of 3, 6, 9 and 12 cm. Production rate and cumulative distillate yield obtained in traditional and developed DSSS at different water depths were compared and best water depth to attain the maximum productivity and cumulative distillate yield was found out.

Results indicated that both traditional and modified double SS produced maximum yield at the minimum water depth of 3 cm. Cumulative distillate yield of the developed SS was 16.39%, 18.86%, 15.22% and 17.07% higher than traditional at water depths of 3, 6, 9 and 12 cm, respectively. Cumulative distillate yield of the developed SS at 3 cm water depth was 73.17% higher than that of the traditional SS at 12 cm depth.

Performance evaluation of DSSS at various water depths by integrating the combined solar operated Vacuum fan and external Condenser.

The purpose of this paper is to compare and contrast two formal models of escalation and de-escalation: the attractor landscape model and the S-shaped reaction function model. Also, the paper aims to enumerate conditions that affect the shape and location of reaction functions and, hence, the stability of less and more escalated states.

Both models are presented together with geometric proofs of the main assertions of the second model. Overlap and comparative strengths of the models are reviewed. Parts of the social science literature are synthesized in a discussion of the antecedents of stability.

Though derived from totally different traditions, these models are similar in their basic assumptions and predictions. Each model has value. The attractor landscape model is easier to grasp and contains a concept of resistance to escalation that is not found in the S-shaped reaction function model. The latter model looks at individual parties rather than the dyad as a whole and, thus, offers an explanation for most of the phenomena described by the former model. It also allows identification of many variables that affect the shape and location of reaction functions and, hence, can be viewed as antecedents of escalation and de-escalation.

Seven testable hypotheses are presented in the Conclusions section. Laboratory tasks for testing such hypotheses have yet to be developed and there is only one study employing real-life measures. However, it is clear that once research on these phenomena really begins, new variables will be found that moderate the strength of the effects hypothesized.

The models provide concepts for thinking about how to avoid runaway escalation and promote runaway de-escalation. The variables mentioned in the hypotheses suggest ways to diminish the likelihood of runaway escalation and can also be used for constructing measures of the likelihood of that phenomenon. The theories also imply that when the likelihood of runaway escalation increases, disputants should be doubly careful to avoid initiating escalative behavior.

The article is original in that the S-shaped reaction function model is refined and further developed and the proofs are new. The comparison between the models is also new, as is most of the enumeration of conditions affecting the stability of low and high escalation. The value of the article is to provide concepts and theory for thinking about escalation and de-escalation, and testable hypotheses for studying these phenomena.

The purpose of this paper is to present a conceptual framework on resilience types in supply chain networks.

Using a complex adaptive systems perspective as an organizing framework, the paper explores three forms of resilience: engineering, ecological and evolutionary and their antecedents and links these to four phases of supply chain resilience (SCRES): readiness, response, recovery, growth and renewal.

Resilient supply chains need all three forms of resilience. Efficiency and system optimization approaches may promote quick recovery after a disruption. However, system-level response requires adaptive capabilities and transformational behaviors may be needed to move supply chains to new fitness levels after a disruption. The three resilience types discussed are not mutually exclusive, but rather complement each other and there are synergies and tradeoffs among these resilience types.

The empirical validation of the theoretical propositions will open up new vistas for supply chain research. Possibilities exist for analyzing and assessing SCRES in multiple and more comprehensive ways.

The findings of the research can help managers refine their approaches to managing supply chain networks. A more balanced approach to supply chain management can reduce the risks and vulnerabilities associated with supply chain disruptions.

This study is unique as it conceptualizes SCRES in multiple ways, thereby extending our understanding of supply chain stability.

This paper aims to present solutions of uncertain linear and non-linear shallow water wave equations. The uncertainty has been taken as interval and one-dimensional interval shallow water wave equations have been solved by homotopy perturbation method (HPM). In this study, basin depth and initial conditions have been taken as interval and the single parametric concept has been used to handle the interval uncertainty.

HPM has been used to solve interval shallow water wave equation with the help of single parametric concept.

Previously, few authors found solution of shallow water wave equations with crisp basin depth and initial conditions. But, in actual sense, the basin depth, as well as initial conditions, may not be found in crisp form. As such, here these are considered as uncertain in term of intervals. Hence, interval linear and non-linear shallow water wave equations are solved in this study using single parametric concept-based HPM.

As mentioned above, uncertainty is must in the above-titled problems due to the various parametrics involved in the governing differential equations. These uncertain parametric values may be considered as interval. To the best of the authors’ knowledge, no work has been reported on the solution of uncertain shallow water wave equations. But when the interval uncertainty is involved in the above differential equation, then direct methods are not available. Accordingly, single parametric concept-based HPM has been applied in this study to handle the said problems.

This study aims to investigate the effect of porous material (clay pots) and it is facing on the productivity performance of a pyramid type solar still. The clay pots are placed in the basin facing up and facing down. The numbers of clay pots considered were 9 and 25, and its performance was compared with normal (0 clay pots) solar still.

The pyramid solar water distillation system has been designed, fabricated and tested under the actual environmental conditions of Kanchikacherla (16.6834 ⁰N, 80.3904 ⁰E), Andhra Pradesh, India. The solar still is used to produce the fresh water and hot water simultaneously from the brackish (i.e. containing dissolved salts) feed water for domestic applications. From open literature, it was established that the rate of evaporation is higher when the flowing water is held for a longer duration on the black color absorber plate, thereby leading to an increase in productivity of freshwater. Therefore, the pyramid solar still has been tested for smooth absorber plate and the absorber plate with porous heat storage material.

The porous material increases the production rate of freshwater compared to a base plate. However, the pyramid still with clay pots has higher productivity at a lower temperature because of the porosity effect.

The total dissolved solids, electrical conductivity and pH of the distilled water and the saline water have also been measured and compared.

This paper aims to deal with the application of variational iteration method and homotopy perturbation method (HPM) for solving one dimensional shallow water equations with crisp and fuzzy uncertain initial conditions.

Firstly, the study solved shallow water equations using variational iteration method and HPM with constant basin depth and crisp initial conditions. Further, the study considered uncertain initial conditions in terms of fuzzy numbers, which leads the governing equations to fuzzy shallow water equations. Then using cut and parametric concepts the study converts fuzzy shallow water equations to crisp form. Then, HPM has been used to solve the fuzzy shallow water equations.

Results obtained by both methods HPM and variational iteration method are compared graphically in crisp case. Solution of fuzzy shallow water equations by HPM are presented in the form triangular fuzzy number plots.

Shallow water equations with crisp and fuzzy initial conditions have been solved.

When complex social-ecological systems collapse and transform, the possible outcomes of this transformation are not set in stone. This paper aims to explore the role of social imagination in determining possible futures for a reformed system. The authors use a historical study of the Luddite response to the Industrial Revolution centred in the UK in the early-19th century to explore the concepts of path dependency, agency and the distributional impacts of systems change.

In this historical study, the authors used the Luddites’ own words and those of their supporters, captured in archival sources (n = 43 unique Luddite statements), to develop hypotheses around the effects on political, social and judicial consequences of a significant systems transformation. The authors then scaffolded these statements using the heuristics of panarchy and basins of attraction to conceptualize this contentious moment of British history.

Rather than a strict cautionary tale, the Luddites’ story illustrates the importance of environmental fit and selection pressures as the skilled workers sought to push the English system to a different basin of attraction. It warns us about the difficulty of a just transition in contentious economic and political conditions.

The Luddites’ story is a cautionary tale for those interested in a just transition, or bottom-up systems transformation generally as the deep basins of attraction that prefer either the status quo or alternate, elite-favouring arrangements can be challenging to shift independent of shocks. While backward looking, the authors intend these discussions to contribute to current debates on the role(s) of social innovation in social and economic policy within increasingly charged or polarized political contexts.

Social innovation itself is often predicated on the need for just transitions of complex adaptive systems (Westley et al., 2013), and the Luddite movement offers us the opportunity to study the distribution effects of a transformative systems change – the Industrial Revolution – and explore two fundamental questions that underpin much social innovation scholarship: how do we build a just future in the face of complexity and what are likely forms those conversations could take, based on historical examples?

This paper aims to solve linear and non-linear shallow water wave equations using homotopy perturbation method (HPM). HPM is a straightforward method to handle linear and non-linear differential equations. As such here, one-dimensional shallow water wave equations have been considered to solve those by HPM. Interesting results are reported when the solutions of linear and non-linear equations are compared.

HPM was used in this study.

Solution of one-dimensional linear and non-linear shallow water wave equations and comparison of linear and non-linear coupled shallow water waves from the results obtained using present method.

Coupled non-linear shallow water wave equations are solved.

Heat and fluid flow through a trapezoidal cooling chamber were studied numerically. Hot fluid is assumed inflow at some depth below the surface into one end of the chamber and withdrawn at another depth from the other end. The top of the chamber is exposed to the surrounding for cooling and the remaining side‐walls are all insulated. Inflow Reynolds number Ro considered is in the range of 100 to 1000 and the inlet densimetric Froude number Fo considered is in the range of 0.5 to 50.0. Numerical experiments show that the flow and temperature fields in the flow‐through trapezoidal chamber are strong function of both Fo and Ro. The submergence ratio D/do, chamber length to depth ratio L/D and chamber wall angles are also significant in influencing the flow fields. Comparisons were also made with available experimental and prototype data.

An interpolation is presented for preparation of input data of water depth in finite element analysis for shallow water problems. The algorithm, computer program for interpolation of water depth and example are shown.