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Socially responsible purchasing (SRP) in the supply chain industry: Meanings and influences
Get PDFOrganisations are increasingly expected to respond to societal and environmental issues within their supply chains. The nuances of this expectation necessitate the consideration of the disparities in corporate social responsibility (CSR) practices within supply chains. Drawing on the stakeholder theory, this paper examines the meanings and influences on socially responsible purchasing (SRP) in supply chains. It adopts an interpretivist qualitative methodology, relying on data from semi-structured, face-to-face interviews with practitioners from multi-national and indigenous organisations in Nigeria. Our findings present a useful understanding of SRP based on the specific endogenous-level and exogenous-level influences. In particular, we develop an encompassing scope for SRP's meaning, outlining its key components, clarifying its boundaries and highlighting inconsistencies in its description. Our study provides a fresh understanding of SRP, with attendant contributions to the broad literature on CSR, corporate governance and supply chain management. It also offers insights to managers, purchasers, suppliers, financial analysts and policy-makers in embedding SRP
Design of Partial Population Experiments with an Application to Spillovers in Tax Compliance
Get PDFWe develop a framework to analyze partial population experiments, a generalization of the cluster experimental design where clusters are assigned to different treatment intensities. Our framework allows for heterogeneity in cluster sizes and outcome distributions. We study the large-sample behavior of OLS estimators and cluster-robust variance estimators and show that (i) ignoring cluster heterogeneity may result in severely underpowered experiments and (ii) the cluster-robust variance estimator may be upward-biased when clusters are heterogeneous. We derive formulas for power, minimum detectable effects, and optimal cluster assignment probabilities. All our results apply to cluster experiments, a particular case of our framework. We set up a potential outcomes framework to interpret the OLS estimands as causal effects. We implement our methods in a large-scale experiment to estimate the direct and spillover effects of a communication campaign on property tax compliance. We find an increase intax compliance among individuals directly targeted with our mailing, as well as compliance spillovers on untreated individuals in clusters with a high proportion of treated taxpayers
An Evaluation of a Novel Air Pollution Abatement System for Ammonia Emissions Reduction in a UK Livestock Building
Get PDFAgriculture and animal feeding operations are responsible for 87% of ammonia emissions in the UK. Controlling NH3 concentrations below 20 ppm is crucial to preserve workers’ and livestock’s well-being. Therefore, ammonia control systems are required for maintaining adequate air quality in livestock facilities. This study assessed the ammonia reduction efficiency of a novel air pollution abatement (APA) system used in a pig farm building. The monitoring duration was 11 weeks. The results were compared with the baseline from a previous pig cycle during the same time of year in 2023. A ventilation-controlled room was monitored during a two-phase campaign, and the actual ammonia concentrations were measured at different locations within the site and at the inlet/outlet of the APA system. A 98% ammonia reduction was achieved at the APA outlet through NH3 absorption in tap water. Ion chromatography analyses of farm water samples revealed NH3 concentrations of up to 530 ppm within 83 days of APA operation. Further scanning electron microscopy and energy-dispersive X-ray inspections revealed the presence of salts and organic/inorganic matter in the solid residues. This research can contribute to meeting current ammonia regulations (NECRs), also by reusing the process water as a potential nitrogen fertiliser in agriculture
The best of times, the worst of times: Continuities in school leaders' work in uncertain times
Get PDFThe COVID 19 pandemic created new challenges for school leaders. They worked very long hours in difficult circumstances. Improvising and responding quickly to poorly timed central guidelines had an adverse effect on their health and wellbeing. Our mixed methods studies show that leaders’ pandemic work was largely directed to establishing new management routines as well as dealing with people. Henri Lefebvre's rhythmanalysis allows us to see that leaders managed their pre-, during and post-pandemic work by working ‘after hours’. The analysis suggests that tackling wellbeing and workload and developing more sustainable leadership careers requires a fundamental redesign of the ways in which leaders’ work is carried out
Giant Elasto-Optic Response of Gallium Selenide on Flexible Mica
Get PDFUnderstanding the bending behaviour of a crystal onto a flexible platform is crucial for flexible electronics. The Young’s modulus, a measure of how easily a material deforms, plays a critical role in the coupled deformation of a crystal on a flexible substrate, as well as the transfer of strain from the substrate onto the layer. Here, we report on the bending behaviour of gallium selenide (GaSe), a van der Waals semiconductor with a small Young’s modulus and strain-dependent electronic band structure. A controllable, reproducible uniaxial strain, ε, is applied to nanometer-thick GaSe layers via their bending on a mica substrate. The spectral shift ∆E of the room temperature photoluminescence emission corresponds to a strain coefficient ∆E/ε of up to ~100 eV, the largest value reported in the literature to date. This is accompanied by coupled electronic and vibrational states under strain-induced resonant excitation conditions, as probed by Raman spectroscopy
An Enhanced Model Predictive Torque Control With Online Loss Minimization Tracking for SPMSM Drive
Get PDFMaximum efficiency per ampere (MEPA) control, also known as loss minimization (LM) control, aims to minimize losses in permanent magnet synchronous machine (PMSM) drive systems by optimizing the dq-axis current references. Addressing the complexities associated with precise drive loss models and the challenges of implementing online optimization for MEPA/LM, this article introduces an enhanced model predictive torque control (MPTC). This new strategy incorporates a reformulated cost function that integrates LM control within the conventional MPTC framework, treating it as a constrained optimization problem. The stability of the proposed MPTC approach is theoretically analyzed using Lyapunov stability theory. Simulation and experimental results validate the control accuracy, dynamic response, and efficiency gains facilitated by this innovative strategy
Inverse Physics-Informed Neural Networks for transport models in porous materials
Get PDFPhysics-Informed Neural Networks (PINN) are a machine learning tool that can be used to solve direct and inverse problems related to models described by Partial Differential Equations by including in the cost function to minimise during training the residual of the differential operator. This paper proposes an adaptive inverse PINN applied to different transport models, from diffusion to advection–diffusion–reaction, and mobile–immobile transport models for porous materials. Once a suitable PINN is established to solve the forward problem, the transport parameters are added as trainable parameters and the reference data is added to the cost function. We find that, for the inverse problem to converge to the correct solution, the different components of the loss function (data misfit, initial conditions, boundary conditions and residual of the transport equation) need to be weighted adaptively as a function of the training iteration (epoch). Similarly, gradients of trainable parameters are scaled at each epoch accordingly. Several examples are presented for different test cases to support our PINN architecture and its scalability and robustness
Inkjet Printed Multifunctional Graphene Sensors for Flexible and Wearable Electronics
Get PDFThe exceptional electrical properties of graphene with high sensitivity to external stimuli make it an ideal candidate for advanced sensing technologies. Inkjet printing of graphene (iGr) can provide a versatile platform for multifunctional sensor manufacturing. Here the multifunctional sensor enabled by combining the design freedom of inkjet printing with the unique properties of graphene networks is reported on. A fully inkjet printed multimaterial device consists of two layers of iGr stripes separated by a dielectric polymeric layer of tripropylene glycol diacrylate (TPGDA). In these devices, the bottom iGr layer, capped with TPGDA, provides temperature sensing, the top uncapped iGr is sensitive to the external atmosphere, while the capacitance between the two iGr layers is sensitive to the applied pressure. The fast, sensitive, and reproducible performance of these sensors are demonstrated in response to environmental stimuli, such as pressure, temperature, humidity, and magnetic field. The devices are capable of simultaneous sensing of multiple factors and are successfully manufactured on a variety of substrates, including Si/SiO2, flexible Kapton films and textiles, demonstrating their potential impact in applications compatible with silicon technologies as well as wearable and healthcare devices
National Approaches to Hydrocarbon Development: Unitization and Unit Operating Agreements
No full textThis book analyses the legal obstacles associated with the advancement of unitization processes and procedures at a national, domestic level.It uses case studies of identified jurisdictions with relevant States practice and unitization experience in terms of the domestic legal framework and practices. For experience in unitization, the book will focus on the following countries: the United States, Canada, the United Kingdom, Norway, Brazil, Mexico, Ghana and Nigeria. Focusing on best practices which have influenced the development of the unitization concept, the book looks at the formulation of different models and operating agreements, and their potential impact on unexplored hydrocarbon resources, particularly in cases where unitization is necessary.The book will be of interest to practitioners, scholars and students in the field of natural resource law, international law and unitization
Euclid preparation: LV. Exploring the properties of proto-clusters in the Simulated Euclid Wide Survey
Get PDFGalaxy proto-clusters are receiving increased interest since most of the processes shaping the structure of clusters of galaxies and their galaxy population happen at the early stages of their formation. The Euclid Survey will provide a unique opportunity to discover a large number of proto-clusters over a large fraction of the sky (14 500 deg2). In this paper, we explore the expected observational properties of proto-clusters in the Euclid Wide Survey by means of theoretical models and simulations. We provide an overview of the predicted proto-cluster extent, galaxy density profiles, mass-richness relations, abundance, and sky-filling as a function of redshift. Useful analytical approximations for the functions of these properties are provided. The focus is on the redshift range z = 1.5-4. In particular we discuss the density contrast with which proto-clusters can be observed against the background in the galaxy distribution if photometric galaxy redshifts are used as supplied by the ESA Euclid mission together with the ground-based photometric surveys. We show that the obtainable detection significance is sufficient to find large numbers of interesting proto-cluster candidates. For quantitative studies, additional spectroscopic follow-up is required to confirm the proto-clusters and establish their richness
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