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Environmental sustainability practices and offshoring activities of multinational corporations across emerging and developed markets
Get PDFYesUsing panel data of 1,080 multinational corporations (MNCs) from the United States, we examine the effects of environmental sustainability practices on the degree of firms’ offshoring activities. In addition, we disaggregate offshoring activities into their core components depending on whether or not the firm buys (inputs) or sells (outputs) and/or owns assets in a given country and examine the extent to which sustainability practices influence the different components of offshoring decisions. The results indicate that sustainability practices significantly affect offshoring activities of MNCs. In particular, we found that sustainable business practices matter when the firm sells goods or owns assets in the given host nation. Additionally, the results show that the sustainability–degree of the internationalization relationship is crucial for MNCs that have offshoring activities in advanced economies relative to those firms that have activities in emerging markets. Our results are robust to alternative explanations
Servitization implementation in the manufacturing organisations: classification of strategies, definitions, benefits and challenges
Get PDFYesThe integration of products and services into a bundled product/service offering by manufacturing
organisations is seen as a global trend in today’s competitive business environment. The shift of
product-based manufacturers towards offering business solutions and value-added services to
consumers is termed as ‘Servitization’. Contrary to the potential benefits expected by adding service
activities to the offerings, advocates voice their concerns towards experiential problems and challenges
in employing the servitization strategy – termed as ‘Servitization Paradox’. Nevertheless, the shift from
product-based delivery to a service-based provision has the potential to significantly impact on
developing sustainable and eco-friendly environment. To provide greater insights to the servitization
phenomenon, this paper presents a comprehensive analysis of the servitization implementation in
manufacturing organisations. In order to respond to the latter, we propose the following three research
questions “Q1 – what are the different types of servitization strategies”, “Q2 – what are the different
servitization definitions”, “Q3 – what are the potential benefits in selecting a servitization strategy?”,
“Q4 – what are the challenges in transitioning towards servitization?”. A systematic literature review
is carried out to understand the past trends and extant patterns/themes in the servitization strategy
research area, evaluate contributions, summarise knowledge, thereby identifying limitations,
implications and potential further research avenues. The key findings confirm servitization studies have
contributed both conceptually and empirically to the development and accumulation of intellectual
wealth to the manufacturing operations and supply chain discipline. Moreover, the findings clearly
indicate the potential of servitization in transitioning manufacturing organisations (e.g. benefits) and
utilising innovative technologies to generate business value. Nevertheless, some voices are backing
further research/development in the area of servitization due to the several existing challenges
Understanding metal concentration and speciation in motorway runoff
No full textYesAlthough highway runoff has historically been extensively studied, the increasing complexity of stormwater management means that there are still significant gaps regarding the reduction of soluble metals. The work reported in this paper addresses these challenges by analysing the presence and behaviour of iron, copper and zinc in runoff from junction 24 of the M1 motorway in the UK (peak traffic flow: 30,000 vehicles per hour) and comparing it with other urban sources of metals found in the same catchment (a local brook and sewage treatment works). The sampling
site included an interceptor and a treatment lagoon and the event monitoring indicated a trend by which the metals did not change their concentration or particulate soluble proportion immediately,
hence showing that pre- and post-storm conditions are important factors when analysing the solubility of metals and their behaviour. The data provided further evidence of the important influence of storm characteristics on metal concentrations in highway runoff, in particular the effects of an antecedent dry weather period (ADWP). In addition, this study also helped us to better understand how the release of sodium the application of de-icer for road maintenance in winter affects the availability of zinc
Experimental analysis of the tensile property of FFF-printed elastomers
Get PDFYesDesigning and manufacturing functional parts with enhanced mechanical property is a major goal of fused filament fabrication (FFF) for polymeric elastomers, which exhibits major advantages in producing such parts with a range of structures. But the unsatisfactory mechanical performance constrains greatly its real application and there is yet no consensus in the mechanical characterization of printed samples. This work takes the nozzle height as the considered factor and tests the tensile property of FFF-printed thermoplastic polyurethane (TPU). Rheological property of the TPU melt, represented here by die swell behavior and shear viscosity, were measured initially to obtain a preliminary assessment of the material suitability and an optimization of melt extrusion conditions for FFF processing. Then correlation between the cross-section profile of deposited bead and the tensile performance of printed sample were evaluated. Both the shape of deposited bead and the bonding strength of two adjacent beads are emphasized when explaining the measured tensile strength. The significance of molecular permeation efficiency at bead-bead interfaces, and bonding-releasing patterns between adjacent beads to the tensile failure of printed objects is discussed.The support provided by China Scholarship Council (CSC, 201806465028) for Xiang Lin during his academic visit in University of Bradford is acknowledged
Branched amphotericin functional poly(N-isopropyl acrylamide): an antifungal polymer
Get PDFYesBranched poly(N-isopropylacrylamide) was functionalized with Amphotericin B (AmB) at the chain ends to produce an antifungal material. The polymer showed antifungal properties against AmB-sensitive strains of Candida albicans, Fusarium keratoplasticum and Aspergillus flavus (minimal inhibitory concentration ranged from 5 to 500 µg ml−1) but was not effective against an AmB resistant strain of C. albicans nor against Candida tropicalis. The polymer end groups bound to the AmB target, ergosterol, and the fluorescence spectrum of a dye used as a solvatochromic probe, Nile red, was blue shifted indicating that segments of the polymer became desolvated on binding. The polymer was less toxic to corneal and renal epithelial cells and explanted corneal tissue than the free drug. Also, the polymer did not induce reactive oxygen species release from peripheral blood mononuclear cells, nor did it cause a substantial release of the proinflammatory cytokines, tumour necrosis factor-α and interleukin-1β (at 0.5 mg ml−1).Welcome Trust DBT Alliance (0998800/B/12/Z) and MRC (UK) (grant no. 16038
Förster resonance energy transfer in fluorophore labeled poly(2-ethyl-2-oxazoline)s†
Get PDFYesDye-functionalized polymers have been extensively studied to understand polymer chain dynamics, intra or inter-molecular association and conformational changes as well as in practical applications such as signal amplification in diagnostic tests and light-harvesting antennas. In this work, the Förster resonance energy transfer (FRET) of dye-functionalized poly(2-ethyl-2-oxazoline) (PEtOx) was studied to evaluate the effect of dye positioning and polymer chain length on the FRET efficiency. Therefore, both α (initiating terminus)- or ω (terminal chain end)-fluorophore single labeled and dual α,ω-fluorescent dye labeled PEtOx were prepared via cationic ring opening polymerization (CROP) using 1-(bromomethyl)pyrene as the initiator and/or 1-pyrenebutyric acid or coumarin 343 as the terminating agent, yielding well-defined PEtOx with high labeling efficiency (over 91%). Fluorescence studies revealed that intramolecular FRET is most efficient for heterotelechelic PEtOx containing both pyrene and coumarin 343 fluorophores as chain ends, as expected. A strong dependence of the energy transfer on the chain length was found for these dual labeled polymers. The polymers were tested in both dilute organic (chloroform) and aqueous media revealing a higher FRET efficiency in water due to the enhanced emissive properties of pyrene. The application of dual labeled polymers as fluorescent probes for temperature sensing was demonstrated based on the lower critical solution temperature behavior of the PEtOx. Furthermore, these polymers could be successfully processed into fibers and thin films. Importantly, the fluorescence properties were retained in the solid state without decreasing the FRET efficiency, thus opening future possibilities for application of these materials in solar cells and/or sensors
Free surface air entrainment and single-bubble movement in supercritical open-channel flow
No full textYesThere has been little study on the microscopic bubble entrainment and diffusion process on the high-speed self-aerated flows although the problem under investigation is theoretically important and has important engineering application. This study presents an experimental investigation on visual processes of free surface air entrainment and single bubble diffusion in supercritical open channel flows. The typical surface deformation, single air bubble rising and penetration are recorded using a high-speed camera system. Results show that for a single bubble formation process, surface entrapment development and bubble entrainment through a deformation evolution underneath the free surface are the two main features. The shape variation of local surface deformation with time follows an identical power law for different bubble size generations. The entrained bubble size depends on both size scale and shape of entrapped free surface. As the single bubble moves downstream, its longitudinal velocity is approximately the same as that of water flow surrounded it, while its vertical velocity for rising and penetration increases with the increase of the water flow velocity. An empirical-linear relationship for the bubble rising and penetration velocity with water flow velocity is obtained. This study demonstrates that the microscopic bubble movement can improve the self-aeration prediction in the open channel flow and advance the knowledge of our understanding of the macroscopic and microscopic air–water properties in hydraulic engineering.National Natural Science Foundation of China (Grant number 51609162), Sichuan Science and Technology Program (Grant number 2019JDTD0007) and the Open funding of the State Key Laboratory of Hydraulics and Mountain River Engineering of Sichuan University (Project No: Skhl1809)
Modelling study of wave damping over a sandy and a silty bed
No full textYesLaboratory experiments have been carried out to investigate wave damping over the seabed, in which the excess pore pressure and free surface elevations are synchronously measured for examining the wave-induced soil dynamics and wave kinematics. Two types of soil, namely fine sand and silt, are tested to examine the role of soil in the wave damping. Observation of experiments shows that (i) soil liquefaction takes place for some tests with silty bed and soil particles suspend into the water layer when the bed is made of silt; (ii) sand ripples can be generated for experiments with sand bed. Measurements reveal that the wave damping greatly depends on the soil dynamic responses to wave loading and the wave damping mechanism over the silty seabed differs from that over the sand bed. On the one hand, the wave damping rate is greatly increased, when soil liquefaction occurs in the silty bed. On the other hand, the presence of sand ripples generated by oscillatory flow in the sand bed experiments also increases the wave damping to some extent. Furthermore, experimental results show that soil particle suspension in the silt bed test contributes to the wave damping. Theoretical analysis is presented to enhance discussions on the wave damping. The theoretical calculations demonstrate that the wave damping is mainly induced by the shear stress in the boundary layer for the cases when no liquefaction occurs. While for the cases when soil liquefaction takes place, the viscous flow in the liquefied layer contributes most towards to the wave damping.National Science Fund for Distinguished Young Scholars (Grant No. 51425901), the National Key Research and Development Program of China (2017YFC1404200), the Marine Renewable Energy Research Project of State Oceanic Administration (GHME2015GC01), and the 111 Project (Grant No. B12032
Hybrid Dynamic Modelling of Engine Emissions on Multi-Physics Simulation Platform
No full textYesThis paper introduces a hybrid dynamic modelling approach for the prediction of NOx emissions for a Diesel engine, based on a multi-physics simulation platform coupling a 1-D air path model (GT-Suite) with in-cylinder combustion model (CMCL Stochastic Reactor Model Engine Suite). The key motivation for this research was the requirement to establish a real time stochastic simulation capability for emissions predictions early in engine development, which required the replacement of the slow combustion chemistry solver (SRM) with an appropriate surrogate model. The novelty of the approach in this research is the introduction of a hybrid approach to metamodeling that combines dynamic experiments for the gas path model with a zonal optimal space-filling design of experiments (DoEs) for the combustion model. The dynamic experiments run on the virtual Diesel engine model (GT- Suite) was used to fit a dynamic model for the parameters required as input to the SRM. Optimal Latin Hypercubes (OLH) DoE run on the SRM model was used to fit a response surface model for the NOx emissions. This surrogate NOx model was then used to replace the computationally expensive SRM simulation, enabling real time simulations of transient drive cycles to be executed. The performance of the proposed approach was validated on a simulated NEDC drive cycle against experimental data collected for the engine case study, which proved the capability of methodology to capture the transient trends for the NOx emissions. The significance of this work is that it provided an efficient approach to the development of a global model with real time transient modelling capability based on the integration of dynamic and local DoE metamodeling experiments
Motivating a linguistically orientated model for a conversational software agent
No full textYesThis paper presents a critical evaluation framework for a linguistically orientated conversational software agent (CSA) (Panesar, 2017). The CSA prototype investigates the integration, intersection and interface of the language, knowledge, and speech act constructions (SAC) based on a grammatical object (Nolan, 2014), and the sub-‐model of belief, desires and intention (BDI) (Rao and Georgeff, 1995) and dialogue management (DM) for natural language processing (NLP). A long-‐standing issue within NLP CSA systems is refining the accuracy of interpretation to provide realistic dialogue to support the human-‐to-‐computer communication.
This prototype constitutes three phase models: (1) a linguistic model based on a functional linguistic theory – Role and Reference Grammar (RRG) (Van Valin Jr, 2005); (2) Agent Cognitive Model with two inner models: (a) knowledge representation model employing conceptual graphs serialised to Resource Description Framework (RDF); (b) a planning model underpinned by BDI concepts (Wooldridge, 2013) and intentionality (Searle, 1983) and rational interaction (Cohen and Levesque, 1990); and (3) a dialogue model employing common ground (Stalnaker, 2002). The evaluation approach for this Java-‐based prototype and its phase models is a multi-‐approach driven by grammatical testing (English language utterances), software engineering and agent practice. A set of evaluation criteria are grouped per phase model, and the testing framework aims to test the interface, intersection and integration of all phase models and their inner models. This multi-‐approach encompasses checking performance both at internal processing, stages per model and post-‐implementation assessments of the goals of RRG, and RRG based specifics tests.
The empirical evaluations demonstrate that the CSA is a proof-‐of-‐concept, demonstrating RRG’s fitness for purpose for describing, and explaining phenomena, language processing and knowledge, and computational adequacy. Contrastingly, evaluations identify the complexity of lower level computational mappings of NL – agent to ontology with semantic gaps, and further addressed by a lexical bridging consideration (Panesar, 2017)