459 research outputs found
Delivering UN Sustainable Development Goals’ Impact on Infrastructure Projects: An Empirical Study of Senior Executives in the UK Construction Sector
Achievement of the United Nations’ 2030 Sustainable Development Goals (SDG) is of paramount importance for both business and society. Across the construction sector, despite evidence that suggests 88% of those surveyed want to measure the SDG impact at both the business and project levels, there continues to be major challenge in achieving this objective. This paper shares the results of a qualitative research study of 40 interviews with executives from the United Kingdom (UK) construction industry. It was supported by a text-based content analysis to strengthen the findings. The results indicate that SDG measurement practices are embraced in principle but are problematic in practice and that rarely does action match rhetoric. While the research was completed in the UK, the findings have broader applicability to other countries since most construction firms have extensive global business footprints. Researchers can use the findings to extend the current understanding of measuring outcomes and impact at project level, and, for practitioners, the study provides insights into the contextual preconditions necessary to achieve the intended outcomes of adopting a mechanism for the measurement of SDGs. The international relevance of this research is inherently linked to the global nature of the SDGs and therefore the results could be used outside of UK
Redefining the Use of Sustainable Development Goals at the Organisation and Project Levels—A Survey of Engineers
The United Nations’ (UN) Sustainable Development Goals (SDGs) aim to deliver an improved future for people, planet and profit. However, they have not gained the required traction at the business and project levels. This article explores how engineers rate and use the SDGs at the organisational and project levels. It adopts the Realist Evaluation’s Context−Mechanism−Outcomes model to critically evaluate practitioners’ views on using SDGs to measure business and project success. The study addresses the thematic areas of sustainability and business models through the theoretical lens of Creating Shared Value and the Triple Bottom Line. A survey of 325 engineers indicated four primary shortfalls for measuring SDGs on infrastructure projects, namely (1) leadership, (2) tools and methods, (3) engineers’ business skills in measuring SDG impact and (4) how project success is too narrowly defined as outputs (such as time, cost and scope) and not outcomes (longer-term local impacts and stakeholder value). The research study is of value to researchers developing business models that address the SDGs and also practitioners in the construction industry who seek to link their investment decisions to the broader outcomes of people, planet and profit through the UN SDGs
Evaluation of the effects of space environment exposure on index of refraction and extinction coefficients of Apollo window materials
Temperature and radiation effects on index of refraction and extinction coefficients of Apollo window material
Observation of noise correlated by the Hawking effect in a water tank
We measured the power spectrum and two-point correlation function for the
randomly fluctuating free surface on the downstream side of a stationary flow
with a maximum Froude number reached above a
localised obstacle. On such a flow the scattering of incident long wavelength
modes is analogous to that responsible for black hole radiation (the Hawking
effect). Our measurements of the noise show a clear correlation between pairs
of modes of opposite energies. We also measure the scattering coefficients by
applying the same analysis of correlations to waves produced by a wave maker.Comment: 11 pages, 14 figures. several points clarified; two new subsections
in the Supplemental Material on the wave equation and the links with
experiments in BEC
Knowledge Based View of University Tech Transfer—A Systematic Literature Review and Meta-Analysis
Research and technology commercialization at research-intensive universities has helped to develop provincial economies resulting in university startups, the growth of other new companies and associated employment. University technology transfer offices (TTOs) oversee the process of technology transfer into the commercial marketplace and these organizational units can be considered in the context of enabling effective knowledge management. However, what enables productive TTO performance has not been comprehensively researched. Therefore, this research study adopted the knowledge-based view as the theoretical construct to support a comprehensive investigation into this area. This was achieved through employing a systematic literature review (SLR) combined with a robust meta-analysis. The SLR identified an initial total of 10,126 articles in the first step of the review process, with 44 studies included in the quantitative synthesis, and 29 quantitative empirical studies selected for the meta-analysis. The research study identified that the relationship between TTO knowledge management and knowledge deployment as well as startup business performance is where TTOs secure the strongest returns
Auger Recombination Lifetime Scaling for Type-I and Quasi-Type-II Core/Shell Quantum Dots
Having already achieved near-unity quantum yields, with promising properties
for light-emitting diode, lasing, and charge separation applications, colloidal
core/shell quantum dots have great technological potential. The shell thickness
and band alignment of the shell and core materials are known to influence the
efficiency of these devices. In many such applications, a key to improving the
efficiency requires a deep understanding of multiexcitonic states. Herein, we
elucidate the shell thickness and band alignment dependencies of the biexciton
Auger recombination lifetime for quasi-type-II CdSe/CdS and type-I CdSe/ZnS
core/shell quantum dots. We find that the biexciton Auger recombination
lifetime increases with the total nanocrystal volume for quasi-type-II CdSe/CdS
core/shell quantum dots and is independent of the shell thickness for type-I
CdSe/ZnS core/shell quantum dots. In order to perform these calculations and
compute Auger recombination lifetimes, we developed a low-scaling approach
based on the stochastic resolution of identity. The numerical approach provided
a framework to study the scaling of the biexciton Auger recombination lifetimes
in terms of the shell thickness dependencies of the exciton radii, Coulomb
couplings, and density of final states in quasi-type-II CdSe/CdS and type-I
CdSe/ZnS core/shell quantum dots.Comment: 7 pages, 4 figure
Electron-hole correlations govern Auger recombination in nanostructures
The fast nonradiative decay of multiexcitonic states via Auger recombination
is a fundamental process affecting a variety of applications based on
semiconductor nanostructures. From a theoretical perspective, the description
of Auger recombination in confined semiconductor nanostructures is a
challenging task due to the large number of valance electrons and exponentially
growing number of excited excitonic and biexcitonic states that are coupled by
the Coulomb interaction. These challenges have restricted the treatment of
Auger recombination to simple, noninteracting electron-hole models. Herein we
present a novel approach for calculating Auger recombination lifetimes in
confined nanostructures having thousands to tens of thousands of electrons,
explicitly including electron-hole interactions. We demonstrate that the
inclusion of electron-hole correlations are imperative to capture the correct
scaling of the Auger recombination lifetime with the size and shape of the
nanostructure. In addition, correlation effects are required to obtain
quantitatively accurate lifetimes even for systems smaller than the exciton
Bohr radius. Neglecting such correlations can result in lifetimes that are 2
orders of magnitude too long. We establish the utility of the new approach for
CdSe quantum dots of varying sizes and for CdSe nanorods of varying diameters
and lengths. Our new approach is the first theoretical method to postdict the
experimentally known universal volume scaling law for quantum dots and makes
novel predictions for the scaling of the Auger recombination lifetimes in
nanorods
Recommended from our members
Resilient Pathways to Atomic Attachment of Quantum Dot Dimers and Artificial Solids from Faceted CdSe Quantum Dot Building Blocks.
The goal of this work is to identify favored pathways for preparation of defect-resilient attached wurtzite CdX (X = S, Se, Te) nanocrystals. We seek guidelines for oriented attachment of faceted nanocrystals that are most likely to yield pairs of nanocrystals with either few or no electronic defects or electronic defects that are in and of themselves desirable and stable. Using a combination of in situ high-resolution transmission electron microscopy (HRTEM) and electronic structure calculations, we evaluate the relative merits of atomic attachment of wurtzite CdSe nanocrystals on the {11Ì…00} or {112Ì…0} family of facets. Pairwise attachment on either facet can lead to perfect interfaces, provided the nanocrystal facets are perfectly flat and the angles between the nanocrystals can adjust during the assembly. Considering defective attachment, we observe for {11Ì…00} facet attachment that only one type of edge dislocation forms, creating deep hole traps. For {112Ì…0} facet attachment, we observe that four distinct types of extended defects form, some of which lead to deep hole traps whereas others only to shallow hole traps. HRTEM movies of the dislocation dynamics show that dislocations at {11Ì…00} interfaces can be removed, albeit slowly. Whereas only some extended defects at {112Ì…0} interfaces could be removed, others were trapped at the interface. Based on these insights, we identify the most resilient pathways to atomic attachment of pairs of wurtzite CdX nanocrystals and consider how these insights can translate to the creation of electronically useful materials from quantum dots with other crystal structures
Diagnostic framework and health check tool for engineering and technology projects
Purpose: Development of a practitioner oriented diagnostic framework and health check tool
to support the robust assessment of engineering and technology projects.
Design/methodology/approach: The research is based on a literature review that draws
together insights on project assessment and critical success factors to establish an integrated
systems view of projects. This is extended to allow a comprehensive diagnostic framework to
be developed along with a high-level health check tool that can be readily deployed on projects.
The utility of the diagnostic framework and health check tool are explored through three
illustrative case studies, with two from Canada and one from the United Kingdom.
Findings and Originality/value: The performance of engineering and technology projects
can be viewed through a systems perspective and being a function of six contributing subsystems
that are: process, technology, resources, impact, knowledge and culture. The diagnostic
framework that is developed through this research integrates these sub-systems to provide a
robust assessment methodology for projects, which is linked to existing best practice for project
reviews, performance management and maturity models. The case studies provide managerial
insights that are related to the diagnostic framework but crucially also position the approach in
the context of industrial applications for construction engineering and technology
management.Research limitations/implications: The case study approach includes two case studies from
the construction and facilities development sector with the third case study from the research
and technology sector. Further work is required to investigate the use of the diagnostic
framework and health check tool in other sectors.
Practical implications: The health check tool will be of practical benefit to new projects
managers that require access to a robust and convenient project review methodology for
assessing the status and health of a given portfolio of projects. The tool can also be used
periodically and throughout the project lifecycle in order to track the performance of projects.
Originality/value: This paper provides a unique view and supporting management framework
to help project managers assess the status and health of projects. Value can be associated with
an extension to the literature on diagnostic tools for engineering project management as well as
the insights provided in the three international case studies, which explore the scope and
applicability of the health check tool to be used in support of projects that have encountered
difficulties and which require implementation of project recovery strategies.Peer Reviewe
Assessing the Impact of Infrastructure Projects on Global Sustainable Development Goals
While sustainability of civil infrastructure is critical to professionals, project owners, regulators, funding agencies and the public, little is done to link individual project sustainability to the United Nation’s 17 global sustainable development goals for 2030. This paper provides some answers but also exposes many questions that need resolution by the infrastructure sector. Using empirical evidence, the authors have identified a ‘golden thread’ between best-practice sustainability-reporting frameworks at project level with those at organisational level. In doing so, they find there is sufficient linkage to embed sustainable-development-goal impact targets into the design stage of an infrastructure project. This would provide a more robust investment appraisal at the project design phase, helping to define project success more widely across the triple bottom line of economic, social and environmental outcomes and associated impact
- …