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Coasts are among the most intensely used environments on the planet, but they also present dynamic and unique hazards, including flooding and erosion. Sea level rise and changing wave climates will alter patterns of erosion and deposition, but some existing coastline evolution models are unable to simulate these effects due to their one-dimensional representation of the systems or the sediment transport processes. In this paper, the development and application of the Coastline Evolution Model 2D (CEM2D) are presented, a model which incorporates these influences. The model has been developed from the established CEM and is capable of simulating fundamental cause–effect relationships in coastal systems. The two-dimensional storage and transport of sediment in CEM2D, which are only done in one-dimension in CEM, mean it is also capable of exploring the influence of a variable water level on sediment transport and the formation and evolution of morphological features and landforms at the mesoscale. The model sits between one-dimensional and three-dimensional models, with the advantage of increased complexity and detail in model outputs compared to the former but with more efficiency and less computational expense than the latter.

Quantitative assessments of wind effects on wave overtopping are carried out using CFD simulations with the open source solver OpenFOAM. The desired wind speeds are achieved efficiently by introducing artificial pressure gradient terms for desired zones inside the computational domain. A new run-time post processing utility has been developed to track the overtopping water over a sea defence. Numerical results are validated using (1) a past experimental study with simple sloped defence and (2) new experiments that were conducted at HR Wallingford with a more realistic structure. Several additional calculations with both small and large water depths reveal that with a high wind speed the overtopping volume can be increased by 30% compared to that without wind. The 2D code is then extended to wave overtopping at a semi-circular beach in the plane as a hypothetical 3D sea defence in order to investigate the 3D effect of wind speeds.

Coasts are among the most intensely used environments on the planet, but they also present dynamic and unique hazards including flooding and erosion. Sea level rise and changing wave climates will alter patterns of erosion and deposition, but some existing coastline evolution models are unable to simulate these effects due to their one-dimensional representation of the systems, or of sediment transport processes. In this paper, the development and application of the Coastline Evolution Model 2D (CEM2D) is presented, that incorporates these influences. The model has been developed from the established CEM model and is capable of simulating fundamental cause-effect relationships in coastal systems. The two-dimensional storage and transport of sediment in CEM2D, which is only done in one-dimension in CEM, means it is also capable of exploring the influence of a variable water level on sediment transport and the formation and evolution of morphological features and landforms at the meso-scale, from 10 to 100 years and over 10 to 100 kilometres. The model sits between one-dimensional and three-dimensional models, with the advantage of increased complexity and detail in model outputs compared to the former, but with more efficiency and less computational expense than the latter.

Wigner time delay in photodetachment from the 3p3/2 and 3p1/2 subshells of Cl− has been studied in the vicinity of the 2p3/2 and 2p1/2 thresholds, using the relativistic random phase approximation (RRPA). The results show time delay spectra dominated by many-body correlations along with very complicated dependence on the energy over a broad spectral range. In addition, the time delay spectra of the two spin-orbit split 3p subshells differ significantly from one another, thereby revealing the importance of relativistic effects even in the case of a low-Z system.

We uncover dramatic variations of the Wigner photoemission time delay with energy and angle in the vicinity of a Fano resonance with the time delay taking opposite signs at different angles at the same energy as well as at the opposite sides of the resonance at the same angle. These variations are illustrated by choosing the Ne 2s→3p autoionizing state as a case study. Moreover, we demonstrate the existence of strikingly significant changes in time delay due to relativistic effects despite Ne being a low-Z atom. This finding shows the possibility for utilizing time delay chronoscopy as a route towards experimental probing of relativistic interactions and the phases of individual transition matrix elements upon atomic photoionization of low- Z atoms. Finally, we develop a practical parametrization to model and explain the angle and energy variation of the autoionizing resonance time delay in the nonrelativistic limit.

Using Cl− as a test case, Wigner time delay in the photodetachment process has been investigated theoretically, along with the photoionization of the isoelectronic Ar atom, for the outer 3p shell using the relativistic-random-phase approximation (RRPA). Time delay was probed in these systems from threshold to 80 eV, to investigate threshold effects, the centrifugal barrier shape resonance, and the Cooper minimum region. This study focuses on Cl − because, for negative ions, the phase of the photoemission process is not dominated by the Coulomb phase as it is in photoionization. The results show significant differences, both qualitative and quantitative, between the time delays for Cl − and Ar photoemission at low photoelectron energy, but they are rather similar in the Cooper minimum region, where the Coulomb phase is small. In particular, the Wigner time delay in Cl − exhibits a dramatic energy dependence just above threshold, and a rapidly increasing time delay in the vicinity of the shape resonance. A strong angular dependence of time delay has also been found near the threshold region for the Cl− case, and is absent in the case of the photoionization of Ar. The origin of these phenomenologies is explained and a prospectus for future work is presented.

Quantitative assessments of wind effects on wave overtopping are carried out using CFD simulations with the open source solver OpenFOAM. The desired wind speeds are achieved efficiently by introducing artificial pressure gradient terms for desired zones inside the computational domain. A new run-time post processing utility has been developed to track the overtopping water over a sea defence. Numerical results are validated using (1) a past experimental study with simple sloped defence and (2) new experiments that were conducted at HR Wallingford with a more realistic structure. Several additional calculations with both small and large water depths reveal that with a high wind speed the overtopping volume can be increased by 30% compared to that without wind. The 2D code is then extended to wave overtopping at a semi-circular beach in the plane as a hypothetical 3D sea defence in order to investigate the 3D effect of wind speeds.

We predict an observable Wigner time delay in outer atomic shell photoionization near inner shell thresholds. The near-threshold increase of time delay is caused by intershell correlation and serves as a sensitive probe of this effect. The time delay increase is present even when the inner and outer shell thresholds are hundreds of electron volts apart. We illustrate this observation by several prototypical examples in noble gas atoms from Ne to Kr. In our study, we employ the random phase approximation with exchange and its relativistic generalization. We also support our findings by a simplified, yet quite insightful, treatment within the lowest-order perturbation theory.

Wigner-Eisenbud-Smith (WES) photoionization time delay is calculated for atomic barium 5s subshell using Relativistic Random Phase Approximation (RRPA), RRPA with relaxation (RRPA-R) and the Relativistic Multi-Configuration Tamm-Dancoff (RMCTD) techniques. Electron correlations are treated differently in different many body methods; the WES time delay is sensitive to these differences. The present study is aimed at determining the suitability of various many-body methods for the study of the WES time-delay

Initial insight into time delay in Mn photoionization in the region of the 3p →, 3d giant autoionization resonance is gained in the framework of the "spin-polarized" random-phase approximation with exchange. The dramatic effect of the giant autoionization resonance on the time delay of photoemission from the 3d and 4s valence subshells of the Mn atom is unraveled. Strong sensitivity of the time delay of the 4s photoemission to the final-state term of the ion remainder [Mn+(4s1,5S) vs Mn+(4s1,7S)] is discovered. It is shown that photoionization time delay in the autoionizing resonance region is explicitly associated with the resonance lifetime, which can thus be directly measured in attosecond time-delay experiments. Similar features are expected to emerge in photoionization time delays of other transition-metal and rare-earth atoms with half-filled subshells that possess giant autoionization resonances as well.

We conduct a systematic study of the dipole phase and the photoelectron group delay (Wigner time delay) in inner shell photoionization of noble gas atoms from Ne to Xe. Our study encompasses the tender x-ray spectral range and extends to 1 keV photoelectron energy. We employ both the relativistic and the nonrelativistic versions of the random-phase approximation with exchange. We identify the long-range Coulomb and short-range Hartree-Fock contributions to the dipole phase which governs the Wigner time delay variation from the threshold to the whole considered range of photoelectron energies.

Retailers use music in the service environment to try to change consumer behaviour with a view to increasing spend, or improving consumer mood. Previous research has largely focused on music but ignored the effects of other noises within a servicescape: yet all noises can impact consumers' affective states, and their behaviour. This study examines the role of both planned and other sounds within the supermarket environment. In particular, this study investigates the cognizant and emotional reactions of supermarket customers, and explores their shopping intentions in the context of shoppers' understanding of and reaction to the sounds they perceive.

Time delay of photoemission from valence ns, np3/2, and np1/2 subshells of noble-gas atoms is theoretically scrutinized within the framework of the dipole relativistic random phase approximation. The focus is on the variation of time delay in the vicinity of the Cooper minima in photoionization of the outer subshells of neon, argon, krypton, and xenon, where the corresponding dipole matrix element changes its sign while passing through a node. It is revealed that the presence of the Cooper minimum in one photoionization channel has a strong effect on time delay in other channels. This is shown to be due to interchannel coupling.

The effects of confinement resonances on photoelectron group delay (Wigner time delay) following ionization of an atom encapsulated inside a C60 cage have been studied theoretically using both relativistic and nonrelativistic random phase approximations.

An analytical formula is developed to represent accurately the photoabsorption cross section of O I for all energies of interest in X-ray spectral modeling. In the vicinity of the Kedge, a Rydberg series expression is used to fit R-matrix results, including important orbital relaxation effects, that accurately predict the absorption oscillator strengths below threshold and merge consistently and continuously to the above-threshold cross section. Further minor adjustments are made to the threshold energies in order to reliably align the atomic Rydberg resonances after consideration of both experimental and observed line positions. At energies far below or above the K-edge region, the formulation is based on both outer- and inner-shell direct photoionization, including significant shake-up and shake-off processes that result in photoionization-excitation and double photoionization contributions to the total cross section. The ultimate purpose for developing a definitive model for oxygen absorption is to resolve standing discrepancies between the astronomically observed and laboratory measured line positions, and between the inferred atomic and molecular oxygen abundances in the interstellar medium from XSTAR and SPEX spectral models.

An analytical formula is developed to represent accurately the photoabsorption cross section of O I for all energies of interest in X-ray spectral modeling. In the vicinity of the Kedge, a Rydberg series expression is used to fit R-matrix results, including important orbital relaxation effects, that accurately predict the absorption oscillator strengths below threshold and merge consistently and continuously to the above-threshold cross section. Further minor adjustments are made to the threshold energies in order to reliably align the atomic Rydberg resonances after consideration of both experimental and observed line positions. At energies far below or above the K-edge region, the formulation is based on both outer- and inner-shell direct photoionization, including significant shake-up and shake-off processes that result in photoionization-excitation and double photoionization contributions to the total cross section. The ultimate purpose for developing a definitive model for oxygen absorption is to resolve standing discrepancies between the astronomically observed and laboratory measured line positions, and between the inferred atomic and molecular oxygen abundances in the interstellar medium from XSTAR and SPEX spectral models.

We present the absolute photoionization cross section of doubly ionized silicon as a function of photon energy. These were obtained by merging a Si2+ ion beam generated in an electron cyclotron resonance source with monochromatized synchrotron radiation from an undulator. The photoion yield measurements were carried out in the photon energy range between 95 eV and 170 eV, i.e., the region corresponding to the excitation followed by the ionization (threshold ∼133.8eV) of an inner-subshell 2p electron. Resonance structure due to 2p excitation in the 2p63s3p3P metastable state was also observed with its contribution to the total cross section not exceeding 3%. Calculation of the 2p photoionization continuum cross section as a function of photon energy was carried out using the relativistic random-phase approximation (RRPA) and agreed very well with the corresponding measurements. The resonance structure in the 3s cross section below the 2p threshold was found to be in good agreement with the multiconfiguration atomic structure calculations of Sayyad et al. [J. Phys. B 28, 1715 (1995)], while the corresponding RRPA-RMQDT (relativistic multi-channel quantum-defect theory) calculations proved less successful.

We have measured the angle-resolved energy dependence of the electrons emitted over the energy range of the triply excited 2s22p2P lithium resonance using synchrotron radiation. We have also calculated the behavior of the angular distribution parameter β using the R-matrix approximation. Experimental and theoretical results are in good agreement and show deep minima in the 1s2p1,3P ionic channels. The energy at which the minima occur does not coincide with the resonance energy, but is shifted towards higher energy.

We present a combined theoretical and experimental investigation of photoionization along the Ne isoelectronic sequence and show that the near-threshold behavior of the cross section for Si4+ differs radically from the nearby ions in the sequence. We demonstrate that the general nature of the underlying physics implies that dramatic changes in near-threshold behavior may be expected for many other ions.

This nickel-base alloy, containing large additions of aluminum and titanium, achieves very high strength at elevated temperature. It has thus received considerable attention for application in components of high performance jet engines such as turbine blades, vanes and nozzles, and even integral turbine wheels. Because of the large quantities of strengthening elements included in the composition, the alloy is not hot worked, and is therefore used in the as-cast condition. Recently, however, there has been considerable development of a powder metallurgy product which permits working of the alloy. At high temperatures the powder-consolidated product becomes superplastic, thus opening many possibilities in fabrication-to-shape of wrought complex components., Supplement 11 to Rept. no. AFML-TR-68-115 Volumes 1 through 4, AD-737 970, AD-737 971, AD-737 972 and AD-737 973.

This volume contains a cumulative reactant species index for MIRADCOM Technical Report H-78-1. Volumes I and II covered data relevant to rare gas and gasmonohalide excimer lasers; Volumes III - VI covered data relevant to nuclear pumped lasers; and Volumes VII - VIII covered additional data relevant to gas lasers. (Author)

This volume and the succeeding volume are the seventh and the eighth in a series that presents data relevant to research and development in the field of gas lasers. The present volumes serve to update most of the areas covered in the previous documents. Those areas not treated here are considered to have been adequately dealt with earlier, as far as immediate data needs are concerned. However, even in those areas where new data are not presented here, references are given to past volumes in order to facilitate access to the previous data. Another function of the present work is to expand somewhat the scope of our data coverage, both with respect to atomic and molecular structural properties and with respect to atomic collisions. New species and sets of collision partners that have recently assumed importance are treated here, and other systems that may become important in the gas laser contex are given attention. A significant amount of new material is also added to the chapter on surface impact phenomena, partly because of current interest in hollow-cathode lasers., See also Volume 8, AD-A101 037.

The present volume serves to update most of the areas covered in the previous documents. Such areas include all nuclear processes, and atomic collisions occurring at high energies, i.e., above about 100 eV impact energy. However, even in those areas where new data are not presented here, references are given to past volumes in order to facilitate access to the previous data. Another function of the present volume is to expand somewhat the scope of our data coverage, both with respect to atomic nd molecular structural properties and with respect to atomic collisions (by the latter term, we mean two- and three- body collisions between electrons, ions, atoms, molecules, and photons at impact energies sufficiently low that nuclear forces are unimportant). New species and sets of collision partners that have recently assumed importance are treated here, and other systems that may become important in the gas laser context are given attention. A significant amount of new material is also added to the chapter on surface impact phenomena, partly because of current interest in hollow-cathode lasers., See also Rept. Nos. RH-77-1, AD-A037 680 and DRSMI-H-78-1-VOL-6, AD-A082 665.

This volume contains a cumulative reactant species index for MIRADCOM Technical Report H-78-1. Volumes I and II covered data relevant to rare gas - rare gas and rare gas - monohalide excimer lasers. Volumes III-V covered data relevant to nuclear pumped lasers. (Author), See also Volume 5, AD-A073 575.

A mathematical analysis was made of the effect of misalinement among the components of rectangular and equiangular strain rosettes on the determination of the magnitudes and directions of principal strains. Misalinements of + or - 2 deg among individual gages introduce no serious errors in the computation of principal strains from rosette data. Errors caused by a given misalinement are proportional to the maximum shear strain at the test point and the effect is most important in regions of pure shear. The equations derived in the analytical investigation provide corrections that are applicable only if the mislinements are known. These equations indicate qualitatively the limits of accuracy with which strain determinations can be made when the possibility of misalinement exists. Verification of the analysis was made by experimental investigation of the behavior of a rosette the misalinement of which was known.

The effects of altitude on the heat dissipation and on the oil pressure drop of an unjacketed and a-conventional jacketed aircraft oil cooler were investigated at altitudes up to 40,000 feet. The investigations covered range of oil flows from 50 to 150 pounds per minute, cooling air flows from 80 to 500 pounds per minute, and oil-inlet temperatures from 1800 to 260 deg F. A method of correlating and of predicting cooling-air pressure drops at altitude has been indicated.

A series of constant strain range tests was made for a wide variety of materials producing fatigue lives varying from a few cycles to about one million cycles. The specimens were subjected to axial, compression-tension, low-frequency fatigue about a zero mean strain. Load range was measured periodically throughout each test, enabling an analysis of fatigue results in terms of elastic, plastic, and total strains. Materials tested were AISI 4130 (soft and hard)., AISI 4340 (annealed and hard), AISI 52100, AISI 304 ELC (annealed and hard), AISI 310 (annealed), AM 350 (annealed and hard), Inconel X, Titanium (6Al-4V), 2014-T6, 5456-H311, and 1100 aluminum, and beryllium.

By the use of orthogonal polynomials developed for discrete sets of data, the least-squares equations for determining the optimized stress-rupture parametric constants are obtained in nearly uncoupled form; thus the use of high-degree polynomials is permitted without the loss of significant figures. Optimum values of the constants can thereby be accurately obtained. The method is applied to the data obtained from the German cooperative long-time creep program by using a general parameter of which the Manson-Haferd and Larson-Miller parameters are special cases. Good correlation was obtained. An analysis is also made of creep data obtained for columbium alloy FS-85 with good results. A complete Fortran IV computer program is included to aid those wishing to use the method.

A method is presented for the determination of the contour of disks, typified by those of aircraft gas turbines, to incorporate arbitrary elastic-stress distributions resulting from either centrifugal or combined centrifugal and thermal effects. The specified stresses may be radial, tangential, or any combination of the two. For example, the equivalent stress may be specified at each radius inasmuch as this stress is generally used as the criterion of the occurrence of plastic flow. Use is made of the finite-difference approach in solving the stress equations, the amount of computation necessary in the evolution of a design being greatly reduced by the judicious selection of point stations and by the aid of a design chart. Use of the charts and of a preselected schedule of point stations is also applied to the direct problem of finding the elastic- and plastic-stress distribution in disks of a given design, thereby effecting a great reduction in the amount of calculation compared with previously published methods. Illustrative examples are presented to show computational procedured in the determination of a new design, and in analyzing an existing design for elastic stress and for stresses resulting from plastic flow.