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The purpose of this paper is to numerically investigate the combined effects of canopy (leaf area index [LAI]) and root properties (root distribution function [Rdf] and root area index [RAI]) on a suction induced in soil-root composite under three different scenarios.

Richards equation coupled with sink term was solved using a commercial finite element package “HYDRUS” to investigate suction induced in soil-root composite.

Scenario 1 unveiled that soil-root composite induces 1 to 20 per cent higher suction than bare soil under the absence of transpiration. From Scenario 2, value of suction at depth of maximum RAI in case of linearly decreasing Rdf was found to be higher than that of other Rdfs. However, depth of suction influence zone (SIZ) for uniform Rdf and non-linear Rdf was found to be 10 and 11 per cent higher than that of linearly decreasing Rdf. Depth of evaporation dominant zone (EDZ) for uniformly decreasing Rdf and non-linear Rdf was found to be 1.08 to 3 times higher than that of linearly decreasing Rdf. From Scenario 3, influence of LAI on depth of SIZ is minimal. Depth of EDZ was found to decrease with the increase in LAI. Based on simple calculation on infinite slope stability, influence of variation in root and shoot properties was found to be significant on its factor of safety.

Numerical constitutive model has limitations that it does not consider aging of plant. This model is only applicable for a particular set of soil conditions. A long-term study is required in this field to further quantify parameters for improving calibration and modeling performance.

Following are the practical implication: consideration of vegetation properties into engineered design of green infrastructure (slopes in this case) and selection of vegetation with appropriate characteristics in design for enhancement of stability of green infrastructure.

Contents of this paper are original, and they have not been submitted to any other journal.

Sustainability has become the topic of the era, and the world is moving toward a circular economy. As part of it, companies are also integrating sustainability in supply chain management. Therefore, this study conducts a technology-empowered systematic literature review to examine the state of the literature on the technologies in the sustainable supply chain. The review reveals that limited studies have been conducted in the area. There is still scope for the researchers to explore new innovative technologies, many clusters in author collaboration, and involve more sectors in the study. Future studies can enrich the field by employing other methodologies like meta-analysis review.

This paper aims to examine the precision loss of ball screw raceway under different operating conditions and geometry parameters.

Based on a new coefficient K’ introduced especially for ball screws to reflect the actual contact condition, the modified Archard theory is applied to ball screws to obtain wear volume of the ball-screw contacts. Thus, the axial precision loss can be defined as the ratio of the wear volume to the contact area. Meanwhile, a novel running bench and a precision-measuring system of ball screws are conducted. Precision variation is obtained and analyzed during the whole life running test, which agrees well with the theoretical values calculated in this paper.

For a given rotational speed, the increasing rate of the precision loss rate is high at low axial load and then becomes small with the increasing axial load, whereas for a given axial load, the precision loss rate is proportional to the rotational speed. Besides, the precision loss rate is reduced with the increasing contact angle between a ball and the screw raceway, and is proportional to the helix angle when the angle changes from 1 to 10 degrees.

The rotational speed used in this experiment is low and the ball screw is of no-load type, although results calculated by the model and Wei’s model seem close when the axial load is high, whether the model built in the paper is applicable to the condition of high rotational speed and preload still needs to be verified in the future work.

This study provides an accurate model to predict the precision loss of the screw raceway and estimate the remaining life of ball screws, which is significant for better performance of ball screws as well as the computer numerical control machine tools.

Previous studies on the wear of ball screws mainly focused on the drag torque analysis and mechanical efficiency estimation, and the experiment to verify their theoretical analysis was almost all limited to the test of drag torque or axial rigidity, which is neither sufficient nor persuasive. However, in this paper, the authors proposed a comprehensive wear prediction model which combines the modified Archard wear theory, Hertz contact theory and kinematic theory of ball screws. To the best of the authors’ knowledge, this kind of study has never been reported in the literature. In addition, for the lack of the test bench and high cost of the experiment, the whole life operation test, which is designed and conducted to confirm the model in this paper, has never been reported in literature either.

This paper aims to provide thermal elastohydrodynamic lubrication (TEHL) contact model to study all balls’ lubrication performance of the ball screw when the multidirectional load is applied.

A new TEHL contact model combining the multidirectional load and the roughness surface texture is established to describe fatigue life of the ball screw. Meanwhile, the authors use the Reynolds equation to study the lubrication performance of the ball screw.

When the multidirectional load is applied, contact load, slide-roll ratio and entrainment velocity of all balls have a periodic shape. The TEHL performance values at the ball-screw contact points including contact stress, shear stress, minimum film thickness and temperature rise are higher than that at the ball-nut contact points. The TEHL performance values increase with the increase of root mean square (RMS) except for the film thickness. In addition, the radial load of the ball screw has a significant effect on the fatigue life.

The results of the studies demonstrate the new TEHL contact model that provides the instructive significance to analyze the fatigue life of the ball screw under the multidirectional load.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2020-0097/

The need to integrate environmental management into supply chains has been recognized recently. Yet, there is a lack of theoretical ground and conceptual framework guiding such efforts to leverage resources and capabilities across supply chain partners. Grounded on stakeholder and resource orchestration theories, the purpose of this paper is to map the emerging practices, develops a theoretical framework, and proposes future research for understanding an emerging best-practice called “green supply chain integration” (GSCI).

A systematic literature review of 142 academic articles is conducted to ensure the process of framework development is auditable and repeatable. The article selection criteria are aligned with the review question ensuring that related theories and practices are identified and evaluated.

The paper illustrates how stakeholder and resource orchestration theories can be used to explain an integrative approach of environmental management in supply chains. The paper identifies four GSCI practices – internal, supplier, customer, and stakeholder GSCI. A theoretical framework and proposition also provide for new directions of research.

The results of this paper are drawn from an extensive review of the existing literature and novel practices that have not been revealed and could have been missed. The emerging practices and theoretical framework can be used for further empirical investigation.

This paper integrates theoretical concepts and empirical findings from the disparate literature and identifies four emerging practices of environmental management by developing a theoretical framework and proposition for future research.

The purpose of this paper is to study the rheological behaviours of lead‐free solder pastes used for flip‐chip assembly applications and to correlate rheological behaviours with the printing performance.

A range of rheological characterization techniques including viscosity, yield stress, oscillatory and creep‐recovery tests were carried out to investigate the rheological properties and behaviours of four different solder paste formulations based on no‐clean flux composition, with different alloy composition, metal content and particle size. A series of printing tests were also conducted to correlate printing performance.

The results show that in the viscosity test, all solder pastes exhibited a shear thinning behaviour in nature with different highest maximum viscosity. The yield stress test has been used to study the effect of temperature on the flow behaviour of solder pastes. A decrease in yield stress value with temperature was observed. The results from the oscillatory test were used to study the solid‐ and liquid‐like behaviours of solder pastes. Creep‐recovery testing showed that the solder paste with smaller particle size exhibited less recovery.

More extensive research is needed to simulate the paste‐roll, aperture‐filling and aperture‐emptying stages of the stencil printing process using rheological test methods.

Implementation of these rheological characterization procedures in product development, process optimization and quality control can contribute significantly to reducing defects in the assembly of flip‐chip devices and subsequently increasing the production yield.

The paper shows how the viscosity, yield stress, oscillatory and creep‐recovery test methods can be successfully used to characterize the flow behaviour of solder pastes and also to predict their performance during the stencil printing process.

To study the effect of Ag content on the melting temperature and wetting properties of Sn‐8.5Zn‐xAg‐0.01Al‐0.1Ga lead‐free Solders.

The solder alloys used in the experiment were Sn‐8.5Zn‐xAg‐0.01Al‐0.1Ga (x=0, 0.1, 0.3, 0.5, 1 and 1.5). In this study, the alloys were initially studied using differential scanning calorimetry to determine their melting temperatures. Afterward, the solderability of the solders was studied using wetting balance and contact angle methods. Moreover, the microstructures of the solders were also investigated with an optical microscope, scanning electron microscope, energy dispersive X‐ray, X‐ray diffraction and electron probe micro analysis.

A small increase in Ag content in the Sn‐8.5Zn‐xAg‐0.01Al‐0.1Ga solders, from 0.1 to 1.0 wt%, has been found to lower their solidus temperature from 198.05°C to 190.20°C. A Ag content of 1.5 wt% increased the solidus temperature of the studied solder systems to 197.79°C. Furthermore, the study also found that the addition of silver lowered the wetting forces of the studied solders. The formation of multi‐intermetallic layers of Cu‐Zn and Ag‐Zn at the interface between the studied solders and copper might explain the reduction of the wetting forces.

The silver contents in the studied Sn‐8.5Zn‐xAg‐0.01Al‐0.1Ga solders were limited to 0, 0.1, 0.3, 0.5, 1.0 and 1.5 wt%.

Useful literature for solder alloy designers and SMT engineers.

The paper provides the answers to the research question of what is the effect of silver content on the melting temperature and wetting properties of Sn‐8.5Zn‐xAg‐0.01Al‐0.1Ga solders.

This paper aims to report on a qualitative comparative case study of coordination in three ongoing research and development projects, each conducted by teams working virtually across multiple, geographically dispersed sites and involving varying degrees of task uncertainty at differing stages on an innovation continuum, from basic fundamental research to scale-up and commercial development.

This study investigated characteristics of effective virtual innovation teamwork, primarily using structured interviews, observation and a limited number of surveys. The analysis was based upon Pava’s (1983) methodology of sociotechnical systems (STS) for non-linear work and was used to assess the influence of virtuality and task uncertainty on the quality of team deliberations and the knowledge development barriers experienced at the various stages on the innovation continuum.

The study identified different technical and social coordination mechanisms and their impact in mitigating knowledge barriers for differing levels of task uncertainty. Technical elements, many based in digital information technology, appeared most significant for coordination where task uncertainty and ambiguity were low. However, with high task uncertainty, the most significant mechanisms were closely tied to the formal and informal social systems of virtual organization.

The key implication for future research is the development of further applications to evaluate this coordination model for modern teamwork in virtual contexts.

The findings extend previous theory about coordination of innovation to include fundamental research and virtual collaboration. Based on the results, a four-step STS methodology for design of virtual team coordination mechanisms was developed and piloted successfully by scientific teams at a prominent North American research laboratory.

This research project has shown that modern STS methodology, updated for non-routine work in a virtual context, can provide a way to assess and mitigate “coordination costs” associated with virtual teamwork. Further, it has identified clear categories of coordination mechanisms that are most effective when teams are working at different stages in the innovation process.

The purpose of this paper is to propose a balanced scorecard (BSC)- and strategy map-based quantitative framework for assessing the lean and green performance of the supply chain (SC). As the SC competitiveness demands efficient and effective utilization of resources throughout the value chain, not only adoption of lean and green SC paradigms but simultaneously its performance evaluation is also vital.

The lean and green SC performance measures are classified into four categories of BSC. A fuzzy decision-making trial and evaluation laboratory (DEMATEL) methodology combined with analytical network process is proposed for examining the causal relationships between BSC perspectives and respective assessment criteria. The application of the proposed assessment framework is demonstrated for the case of Indian textile SC.

The research delivers a quantitative assessment framework for evaluating lean and green performance of the SC. The results obtained for a typical case of Indian textile SC revealed that “delivery performance,” “profitability” and “operational cost” are the most crucial performance measures. The perspective of “internal processes” is the most significant of all BSC perspectives while “learning and growth” perspective acts as the driving force to improve lean and green SC performance.

The paper makes two contributions in the domain of lean and green assessment of SC performance. First, it proposes an evaluation framework to investigate into the causal relationships among the BSC perspectives and related factors. Second, it undertakes an empirical investigation for Indian textile SC to develop key managerial insights and provide policy-related recommendations.

Although risks and client‐vendor relationships in IT outsourcing have been studied in prior research, there is a paucity of studies providing insights on the mitigation of client risks through the relationship. This research aims to focus on mitigation of the ex post risks of firms engaged in offshore software development (OSD). Client risks due to service provider behavior are identified first. Further, this work seeks to identify relationship variables that could reduce the impact of determinants of risk on a risk category.

This research followed a multiple case study method aiming to build insights and directions that would facilitate further research. The paper's goal of sampling was to choose cases which were likely to extend the emergent theory pertaining to risks and their mitigation through relationships.

Findings from this study show that shirking, loss of control over information assets, and service provider lock‐in are the three categories of ex post risks. A relationship management strategy ensuring reasonable profits to the vendor could mitigate shirking risk. Trustworthiness of vendors established through credibility and benevolence in prior engagements could mitigate the risk of loss of control over information assets. Further, dependence balancing through a multi‐vendor offshoring strategy and joint investments in relationship‐specific assets could mitigate the risk of service provider lock‐in.

The findings from this research provide useful insights in vendor selection and management process.

This paper adds to the growing body of literature in offshore IT outsourcing and makes two significant contributions: identification and categorization of risks due to vendor behavior and their determinants in OSD; and understanding the role of relationship dimension in mitigating such risks in OSD.