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This paper aims to study the frictional performance of reciprocating pair with high velocity by using hydrodynamic lubrication principle and fish scale textured piston model.

Based on the idea of function characteristic approximation and coordinate change, a mathematical representation model of imitating fish scale texture pit section is established. According to the principle of dynamic pressure lubrication of the textured fluid, a three-dimensional numerical model of flow field for fish scale texture is established without considering cavitation. Numerical analysis of the model carp scale texture unit by orthogonal experimental design and FLUENT software is carried out.

Effects of fish scale pit texture on friction properties for a reciprocating pair piston surface with high velocity (impact piston) are acquired. Effects of texture characterization parameters and flow rate on the surface friction performance for impact piston are found. Effects of different characteristic parameters combination of imitating fish scale texture on friction performance for impact piston surface are obtained.

The model is an effective tool to study the friction and wear of reciprocating pair with high velocity. The effects of fish scale textured piston pair supply a theory lead to design the reciprocating pair with better friction performance.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2019-0398

This study aims to analyze the influence of farmers’ degree of participation in collective action on their adoption decisions and waiting time regarding soil and water conservation (SWC) measures.

The Probit model and Generalized Propensity Score Match method are used to assess the effect of the degree of participation in collective action on farmers’ adoption decisions and waiting time for implementing SWC measures.

The findings reveal that farmers’ engagement in collective action positively influences the decision-making process regarding terrace construction, water-saving irrigation and afforestation measures. However, it does not significantly impact the decision-making process for plastic film and ridge-furrow tillage practices. Notably, collective action has the strongest influence on farmers’ adoption decisions regarding water-saving irrigation technology, with a relatively smaller influence on the adoption of afforestation and terrace measures. Moreover, the results suggest that participating in collective action effectively reduces the waiting time for terrace construction and expedites the adoption of afforestation and water-saving irrigation technology. Specifically, collective action has a significantly negative effect on the waiting time for terrace construction, followed by water-saving irrigation technology and afforestation measures.

The results of this study underscore the significance of fostering mutual assistance and cooperation mechanisms among farmers, as they can pave the way for raising funds and labor, cultivating elite farmers, attracting skilled labor to rural areas, enhancing the adoption rate and expediting the implementation of terraces, water-saving irrigation technology and afforestation measures.

Drawing on an evaluation of farmers’ degree of participation in collective action, this paper investigates the effect of participation on their SWC adoption decisions and waiting times, thereby offering theoretical and practical insights into soil erosion control in the Loess Plateau.

In this chapter it is shown how economic evaluation algorithms of water use can be integrated into a long-term water management model such that surface-water availability and economic evaluation of various levels of water availability to different uses can be modeled simultaneously. This approach makes it possible to include essential features of economic analyses of water use into water resource modeling and thus improves the capability of such models to support decision making in water management. This is especially relevant for the implementation of the Water Framework Directive, which requires economic analyses to be included in the decision process about future water management strategies.

The water management simulation model WBalMo is presented and the integration of economic-evaluation algorithms is demonstrated for the examples of surface-water use for fish farming and for filling open-cast mining pits in order to achieve acceptable water-quality levels in the emerging pit lakes. Results of applying this integrated evaluation approach are shown for different water management scenarios under conditions of global change in the East German Spree and Schwarze Elster river basins, where water scarcity is an urgent issue. Among the lessons which are drawn by the authors one lesson reads that integrating economic evaluation algorithms into a pre-existing model might bring enormous problems. Therefore, such model approaches should be developed together by water engineers and economists in an interdisciplinary endeavor right from the start.

This chapter describes the scenario technique used for the integrative methodological approach (IMA) of the German global change project GLOWA Elbe. It is outlined how regional scenarios are systematically derived to analyze water use conflicts and their resolution in the context of global change for the German Elbe river basin. Through the combination of frameworks of development and policy strategies a consistent set of developmental scenarios can be generated that makes it possible to examine the regional impact of policy strategies under conditions of different future global change development paths. The scenario analysis of the framework of development starts on the global level with qualitative IPCC storylines, translates them to the regional level, and quantifies their regional effects by means of modeling and statistical estimation methods. The policy strategies are derived in close cooperation with regional stakeholders.

This chapter examines the manner in which a disaster-affected population of artisanal fishers relocated inland to new sites following the Indian Ocean tsunami of 2004 experienced and adapted to problems of water quality, scarcity, sanitation, and drainage. While numerous studies of conflicts over water tend to focus on issues of equitable access (see Anand, 2011), this chapter seeks to link the problem to the contested priorities driving land and resource use and access. I show how inland relocation negatively impacted households, making it harder to sustain livelihoods due to distance from the coast, while imposing new costs including that of commodified and scarce water, locational deficiencies, and the structural weaknesses of new housing. Placed in a historical context, the problem of water can be seen as an aspect of the long-term problem of ecologically unequal exchange pitting local artisanal fisher communities against an aggressively state-supported commercial fishery sector. The continuity I seek to hone in on is the pattern of imposing costs on fishers while enabling the alienation and privatization of coastal resources. Taking water not only as a vital substance presenting questions of access and quality but also as a problem of drainage and effluence enables a fuller consideration of how the unequal distribution of costs on poorer populations became legitimized in the name of recovery. At the same time, the chapter also highlights the manner in which fishers refused to remain docile subjects of power and used their agency and autonomy in adapting to and sometimes refusing the terms of relocation.

Introduction Although nickel is generally regarded as a corrosion resistant material its resistance to sea water is only moderate. In fast flowing sea water its corrosion rate is very low; of the order of 0.0005 in/yr. Under stagnant conditions, however, it is susceptible to pitting and crevice corrosion attack. Consequently, alloying has been a common method of improving corrosion resistance to obtain a material having the excellent resistance of nickel to fast flowing sea water together with an improved resistance to pitting corrosion.

Anthropologists who study disasters share the widely acknowledged understanding that the effects of disasters tend to be more severe among economically and socially marginalized communities than others. Moreover, while poverty intensifies the effects of disasters, it also places survivors at the mercy of policies they have little control over because they often tend to be socially and politically marginalized on account of their poverty. Social vulnerability in other words is a determining factor in shaping the vulnerability of populations to catastrophic events. While scholars tend to focus on the catastrophic event itself as the locus of analysis, it has also become amply clear that such studies need to be in conversation with those that explore the long-term trajectories and effects of social inequality. Drawing upon fieldwork conducted in southern India among artisanal fisher communities affected by the tsunami of 2004, this paper argues that the conceptual aims and claims of the vulnerability concept ought to be extended beyond the confines of the disaster (conceptualized as event), to the broader historical sweep of unequal social relations of production, exchange and consumption within which such communities find themselves. Positioned at a disadvantage in relation to powerful players such as the state, multilateral entities and private big capital, such communities nevertheless might also become important loci of possibility, as they bring to bear their own critiques of power, and fashion political strategies that often frustrate and undermine the conceptual frameworks and goals of contemporary capitalist-led development.

Drawing on identity theory and the symbolic interactionism perspective of identity theory, this study aims to construct a moderated mediation framework to test the effects of perceived overqualification (POQ) on knowledge sharing (KS) through professional identity threat (PIT) and the moderating role of coworkers' help-seeking behavior (CHSB).

This paper uses a quantitative multistudy research design with a combination of a scenario experiment (Study 1) and a two-wave field study among 220 supervisor-subordinate dyads at a power company in China. Using analysis of variance, confirmatory factor analysis (CFA) and bootstrapping method, the authors validated the research hypothesis.

In the scenario experiment study (study 1), the authors find that POQ is positively related to PIT and that CHSB negatively moderates the positive impact of POQ on PIT. The field study (study 2) replicated the above findings and found that PIT mediates the negative effect of POQ on KS. In addition, CHSB negatively moderates the mediating role of PIT between POQ and KS.

First, the current study extended the nomological network of POQ research by examining its influence on employees' KS. Second, this study empirically investigated the mediating role of PIT, which provided a new explanatory mechanism for the influence of POQ. Finally, this study demonstrates the moderating role of CHSB—a situational factor that has been ignored in previous studies.

This chapter examines the Netherlands’ challenges in safeguarding its low-lying coastline against rising sea levels and the consequences of coastal defense strategies on marine life, particularly in relation to SDG14. Sea-level rise necessitates increased soft coastal defense strategies, affecting seafloor areas and marine biodiversity through sand extraction and sand nourishments. The use of hard structures for coastal defense contributes to the loss of natural coastal habitats, raising biodiversity concerns. The chapter explores the potential benefits of artificial hard surfaces as marine habitats, emphasising the need for careful design to prevent ecological problems caused by invasive species. Strategies for enhancing biodiversity on human-made hard substrate structures, including material variations, hole drilling, and adaptations, are discussed. The ecological impact of marine sand extraction is examined, detailing its effects on benthic fauna, sediment characteristics, primary production, and fish and shrimp populations. Solutions proposed include improved design for mining areas, ecosystem-based rules for extraction sites, and ecologically enriched extraction areas. The ecosystem effects of marine sand nourishments are also analysed, considering the impact on habitat suitability for various species. The chemical effects of anaerobic sediment and recovery challenges are addressed. Mitigation measures, such as strategic nourishment location and timing, adherence to local morphology, and technical solutions, are suggested. The chapter underscores the importance of education in Nature-based Solutions and announces the launch of a new BSc programme in Marine Sciences at Wageningen University & Research, integrating social and ecological knowledge to address challenges in seas, oceans, and coastal regions and support SDG14 goals.