The 8th flow - common understanding

Projects are a form of engineered-to-order (ETO) production which require that the definition of Value becomes part of the production process. Project production requires the inclusion of the product design, the design process, and the production process to be integrated in order to fully benefit from waste reduction and process improvement. In construction, project production is more challenging because of the temporal, transient, and fragmented nature of the project team and the supporting supply chain. This requires a form of ‘interoperability’ between the supply chain organisations, the particular teams involved, the commissioning clients and other stakeholders. It is proposed that this ‘interoperability’ is a form of common understanding and that this understanding needs to be defined, developed, and nurtured across the project execution as a flow in the same way that other flows are managed. Building on the seven flow model proposal reported by Koskela and Howell (1999), this paper proposes a common understanding as an eighth flow and suggests how it might be managed. The paper classifies the concept of common understanding as a soft flow and shows that although it is a fresh insight it actually has roots in lean production. The identity of common understanding as the eighth flow arises from a number of funded research projects in which the difficulties of lean construction implementation were investigated

New Developments in Hyperbaric Oxygen Therapy

Hyperbaric Oxygen Therapy, or HBOT, is a form of treatment based on the inhalation of 100% pure oxygen while subjected to closed chamber or room at pressures greater than sea level (1 atmosphere, ATA) (Howell et al., 2018; Kocaman, 2020). HBOT is administered through either a mono-place chamber or a multi-place chamber. Mono-place chambers are pressurized with oxygen and are equipped to handle a single person at a time. Multi-place chambers, on the other hand, can accommodate up to 20 people at a time, including medical personnel and intubated patients. These chambers are pressurized with air, and pure oxygen is administered via facemask, hood tent, or endotracheal tube (Gill & Bell, 2004; Howell et al., 2018). Oxygen is primarily used by the body in the formation of ATP, the molecule responsible for fueling cellular processes. When body tissues are injured or damaged, the energetic demand increases, and consequently more oxygen is needed (Kahle & Cooper, 2020). HBOT increases the body’s arterial and tissue oxygen tension, augmenting the amount of oxygen that the blood plasma can carry. This can create a number of beneficial biochemical, cellular, and physiologic effects (Tibbles & Edelsberg, 1996)

The qudit Pauli group: non-commuting pairs, non-commuting sets, and structure theorems

Qudits with local dimension $d>2$ can have unique structure and uses that qubits ($d=2$) cannot. Qudit Pauli operators provide a very useful basis of the space of qudit states and operators. We study the structure of the qudit Pauli group for any, including composite, $d$ in several ways. For any specified set of commutation relations, we construct a set of qudit Paulis satisfying those relations. We also study the maximum size of sets of Paulis that mutually non-commute and sets that non-commute in pairs. Finally, we give methods to find near minimal generating sets of Pauli subgroups, calculate the sizes of Pauli subgroups, and find bases of logical operators for qudit stabilizer codes. Useful tools in this study are normal forms from linear algebra over commutative rings, including the Smith normal form, alternating Smith normal form, and Howell normal form of matrices.Comment: 35 pages, 1 figur

The evolution of a slender non-axisymmetric drop in an extensional flow

An asymptotic method for analysing slender non-axisymmetric drops, bubbles and jets in a general straining flow is developed. The method relies on the slenderness of the geometry to reduce the three-dimensional equations to a sequence of weakly coupled, quasi-two-dimensional Stokes flow problems for the cross-sectional evolution. Exact solution techniques for the flow outside a bubble in two-dimensional Stokes flow are generalised to solve for the transverse flow field, allowing large non-axisymmetric deformations to be described. A generalisation to the case where the interior contains a slightly viscous fluid is also presented. Our method is used to compute steady non-axisymmetric solution branches for inviscid bubbles and slightly viscous drops. We also present unsteady numerical solutions showing how the eccentricity of the cross-section adjusts to a non-axisymmetric external flow. Finally, we use our theory to investigate how the pinch-off of a jet of relatively inviscid fluid is affected by a two-dimensional straining cross-flow

Mathematical modelling of the overflowing cylinder experiment

The overflowing cylinder (OFC) is an experimental apparatus designed to generate a controlled straining flow at a free surface, whose dynamic properties may then be investigated. Surfactant solution is pumped up slowly through a vertical cylinder. On reaching the top, the liquid forms a flat free surface which expands radially before overflowing down the side of the cylinder. The velocity, surface tension and surfactant concentration on the expanding free surface are measured using a variety of non-invasive techniques. A mathematical model for the OFC has been previously derived by Breward, Darton, Howell and Ockendon and shown to give satisfactory agreement with experimental results. However, a puzzling indeterminacy in the model renders it unable to predict one scalar parameter (e.g. the surfactant concentration at the centre of the cylinder), which must be therefore be taken from the experiments. In this paper we analyse the OFC model asymptotically and numerically. We show that solutions typically develop one of two possible singularities. In the first, the surface concentration of surfactant reaches zero a finite distance from the cylinder axis, while the surface velocity tends to infinity there. In the second, the surfactant concentration is exponentially large and a stagnation point forms just inside the rim of the cylinder. We propose a criterion for selecting the free parameter, based on the elimination of both singularities, and show that it leads to good agreement with experimental results

Sedimentology and reservoir properties of tabular and erosive offshore transition deposits in wave-dominated, shallow-marine strata : Book cliffs, USA

Acknowledgements and Funding Funding for this study was provided from the Research Council of Norway (Petromaks project 193059) and the FORCE Safari project. The helicopter-LiDAR data was collected by J. Valet and S. Pitiot of Helimap System SA. Riegl LMS GmbH is acknowledged for software support for the outcrop models, and ROXAR is acknowledged for use of their RMS reservoir modelling package. A. Rittersbacher is acknowledged for processing the heli-LiDAR model. The first author would like to thank O. S. Mulelid-Tynes and G. Henstra for assistance in the field and for valuable discussions. G. Hampson is thanked for insightful comments that significantly improved this manuscriptPeer reviewedPostprin

Mathematical modelling of non-axisymmetric capillary tube drawing

This paper concerns the manufacture of non-axisymmetric capillary tubing via the Velloprocess, in which molten glass is fed through a die and drawn off vertically. The shapeof the cross-section evolves under surface tension as it flows downstream. The aim is to achieve a given desired final shape, typically square or rectangular, and our goal is to determine the required die shape. We use the result that, provided the tube is slowly varying in the axial direction, each cross-section evolves like a two-dimensional Stokes flow when expressed in suitably scaled Lagrangian coordinates. This allows us to use a previously derived model for the surface- tension-driven evolution of a thin two-dimensional viscous tube. We thus obtain, and solve analytically, equations governing the axial velocity, thickness and circumference of the tube, as well as its shape. The model is extended to include non-isothermal effects

Straining flow of a micellar surfactant solution

We present a mathematical model describing the distribution of monomer and micellar surfactant in a steady straining flow beneath a fixed free surface. The model includes adsorption of monomer surfactant at the surface and a single-step reaction whereby $n$ monomer molecules combine to form each micelle. The equations are analysed asymptotically and numerically and the results are compared with experiments. Previous studies of such systems have often assumed equilibrium between the monomer and micellar phases, i.e. that the reaction rate is effectively infinite. Our analysis shows that such an approach inevitably fails under certain physical conditions and also cannot accurately match some experimental results. Our theory provides an improved fit with experiments and allows the reaction rates to be estimated

VV Pup in a low state: secondary-star irradiation or stellar activity?

Aims. Emission lines in polars show complex profiles with multiple components that are typically ascribed to the accretion stream, threading region, accretion spot, and the irradiated secondary-star. In low-state polars the fractional contribution by the accretion stream, and the accretion spot is greatly reduced offering an opportunity to study the effect of the secondary-star irradiation or stellar activity. We observed VV Pup during an exceptional low-state to study and constrain the properties of the line-forming regions and to search for evidence of chromospheric activity and/or irradiation. Methods. We obtained phase-resolved optical spectra at the ESO VLT+FORS1 with the aim of analyzing the emission line profile and radial velocity as a function of the orbital period. We also tailored irradiated secondary-star models to compare the predicted and the observed emission lines and to establish the nature of the line-forming regions. Results. Our observations and data analysis, when combined with models of the irradiated secondary-star, show that, while the weak low ionization metal lines (FeI and MgI) may be consistent with irradiation processes, the dominant Balmer H emission lines, as well as NaI and HeI, cannot be reproduced by the irradiated secondary-star models. We favor the secondary-star chromospheric activity as the main forming region and cause of the observed H, NaI, and He emission lines, though a threading region very close to the L1 point cannot be excluded.Comment: 10 pages, 9 figures, in press on A&