New Concepts For Preliminary Hydropower Design: The Powermax Slope, Binary Turbine Sizing, and Static Regain

In Utah during the 1960s, the cost of producing electrical energy was as much, or in some cases more, by hydroelectric generation than by plants using steam from coal fired boilers. The relatively high hydropower cost was generally attributed to maintenance and replacement costs associated with plants that had been build in the 1920s. Utah Power & Light Company during the 1960 period decided not to renew power licenses and to abandon many small hdyroplants. Since 1973, rising coal and related fossil fuel costs have caused steam generation costs to accelerate and have made hydroelectric generation relatively more attractive. However, the capital cost of replacing deteriorated pipelines and restoring plants to production capability is high, and the prospect of large capital investment during periods of high interest rates creates a hesitancy to renovate existing or to construct new small hydro units. The cost analysis to replace abandoned plants or to construct new plants has been generally based on restoring an existing configuration or building to design standards in use at the time of the original structure. The traditional design method was to design a pipeline on a flat slope with a relatively large pipe diameter. This method maximized head, but minimized the flow. The resultant energy was therefore less than the potential, but constant. This method also confined the variations in flow to a range that could be handled by a single, or the most two, variable geometry turbines. The flow point on the typical flow duration curve for western mountain streams where the ratio of maximum to minimum flow variation is 4 to 1 or less is at is at or near the 25 percent exceedance level. It is shown in this report that the same diameter pipeline as used in traditional design can by sloped to maximize the power output of the plant (powermax slope) and thus increase the annual energy production by 149 to 186 percent, the difference being dependent upon the amount of energy recovered by the static regain in pressure pipelines when flows are reduced below the maximum. This optimized flow and head without changing the cost of the pipeline. The effect is to reduce the unit cost of energy produced. The higher flow at the powermax slope has a greater variability and will therefore require turbines with greater variability. It is demonstrated that multiple fixed geometry turbines sized in binary steps can effectively span flow variability ratios from 10 to 1 or greater and be installed at less cost than custom designed variable geometry units. Thus, designing at the points on the flow duration curve corresponding to the 10 percent or lower exceedance level is economically feasible. Combining the powermax concept for pipelines with the concept of using binary sized turbines and a pressure system to use the static regain concept can result in hydro plant designs that utilize a greater portion of the potential energy at a given site and reduce the unit cost of energy

S1×S2S^1 \times S^2 wormholes and topological charge

I investigate solutions to the Euclidean Einstein-matter field equations with topology $S^1 \times S^2 \times R$ in a theory with a massless periodic scalar field and electromagnetism. These solutions carry winding number of the periodic scalar as well as magnetic flux. They induce violations of a quasi-topological conservation law which conserves the product of magnetic flux and winding number on the background spacetime. I extend these solutions to a model with stable loops of superconducting cosmic string, and interpret them as contributing to the decay of such loops.Comment: 18 pages (includes 6 figs.), harvmac and epsf, CU-TP-62

Traveling with Companions: The Social Customer Journey

When customers journey from a need to a purchase decision and beyond, they rarely do so alone. This article introduces the social customer journey, which extends prior perspectives on the path to purchase by explicitly integrating the important role that social others play throughout the journey. The authors highlight the importance of “traveling companions,” who interact with the decision maker through one or more phases of the journey, and they argue that the social distance between the companion(s) and the decision maker is an important factor in how social influence affects that journey. They also consider customer journeys made by decision-making units consisting of multiple individuals and increasingly including artificial intelligence agents that can serve as surrogates for social others. The social customer journey concept integrates prior findings on social influences and customer journeys and highlights opportunities for new research within and across the various stages. Finally, the authors discuss several actionable marketing implications relevant to organizations’ engagement in the social customer journey, including managing influencers, shaping social interactions, and deploying technologies

Production of Designer Mabe Pearls in the Black-lipped Pearl Oyster, Pinctada margaritifera, and the Winged Pearl Oyster, Pteria penguin, from Andaman and Nicobar Islands, India

The black-lipped pearl oyster, Pinctada margaritifera, is sporadically distributed in the Indo-Pacific region, where they have been traditionally used for food, ornaments, jewelry, tools, and more recently for the production of black pearls (Lane et al. 2003). During the past two decades, black pearl farming programs have been initiated by several nations and are now at various levels of productio

The early Aurignacian dispersal of modern humans into westernmost Eurasia

Documenting the first appearance of modern humans in a given region is key to understanding the dispersal process and the replacement or assimilation of indigenous human populations such as the Neanderthals. The Iberian Peninsula was the last refuge of Neanderthal populations as modern humans advanced across Eurasia. Here we present evidence of an early Aurignacian occupation at Lapa do Picareiro in central Portugal. Diagnostic artifacts were found in a sealed stratigraphic layer dated 41.1 to 38.1 ka cal BP, documenting a modern human presence on the western margin of Iberia ∼5,000 years earlier than previously known. The data indicate a rapid modern human dispersal across southern Europe, reaching the westernmost edge where Neanderthals were thought to persist. The results support the notion of a mosaic process of modern human dispersal and replacement of indigenous Neanderthal populations.BCS-1420299 / BCS-1724997 / BCS-1420453 / BCS-1725015 / SGS-2020-017 / DL 57/2016/CP1361/CT0026 / IF/01075/2013info:eu-repo/semantics/publishedVersio

Off-Shell Rho-Omega Mixing Through Quark Loops With Non-Perturbative Meson Vertex And Quark Mass Functions

The momemtum dependence of the off-shell $\rho$-$\omega$ mixing amplitude is calculated through a two-quark loop diagram, using non-perturbative meson-quark vertex functions for the $\rho$ and $\omega$ mesons, as well as non-perturbative quark propagators. Both these quantities are generated self-consistently through an interlinked BSE-cum-SDE approach with a 3D support for the BSE kernel with two basic constants which are pre- checked against a wide cross section of both meson and baryon spectra within a common structural framework for their respective 3D BSE's. With this pre-calibration, the on-shell strength works out at -2.434$\delta(m_q^2)$ in units of the change in "constituent mass squared", which is consistent with the $e^+e^-$ to $\pi^+\pi^-$ data for a u-d mass difference of ~4 MeV ,while the relative off-shell strength (0.99 $\pm$ 0.01) lies midway between quark-loop and QCD-SR results. We also calculate the photon-mediated $\rho$-$\omega$ propagator whose off-shell structure has an additional pole at $q^2$=0. The implications of these results vis-a-vis related investigations are discussed.Comment: 12 Pages, latex file, NTUTH-94-0