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This article presents findings from a Computational Fluid Dynamics (CFD) study performed on the heat transfer characteristics of diesel and partially-premixed combustion (PPC) engines. The study is confined to the combustion bowl, where numerical simulations have been performed on a part of the engine cycle, namely the compression, combustion, and expansion phases. Three engine geometries were sim

In this work, we present a novel formulation for efficient estimation of group-sparse regression problems. By relaxing a covariance fitting criteria commonly used in array signal processing, we derive a generalization of the recent SPICE method for grouped variables. Such a formulation circumvents cumbersome model order estimation, while being inherently hyperparameter-free. We derive an implement

Exposure to inorganic arsenic (iAs) is a risk factor for cancer. Alterations in mitochondrial DNA copy number (mtDNAcn) and telomere length (TL) have been associated with cancer risk. Two Argentinean groups were studied: A) Puna area of Andes and B) Chaco. Arsenic exposure was assessed as the sum of arsenic metabolites (iAs, MMA, and DMA) in urine (U-As) using HPLC-HG-ICPMS. MtDNAcn, TL, and genot

There is a battle in the supermarket isle, a battle between what the consumer wants and what the retailer and others want her to see, and subsequently to buy. Product packages and displays contain a number of features and attributes tailored to catch consumers' attention. These are what we call external factors comprising the visual saliency, the number of facings, and the placement of each produc

The arsenic adsorption characteristics of a macroporous polymer coated with coprecipi-tated iron-aluminium hydroxides (MHCMP) is evaluated in this study. The MHCMP had a maximum adsorption capacity of 82.3 and 49.6 mg As/g adsorbent for As(III) and As(V) ions respectively. Extended X-ray Absorption Fine Structure (EXAFS) confirmed that binding of As(III) ions took place on the iron hydroxides coat

We study the effect of managerial power on CEOs' tendency to imprint their personal leverage preferences upon the firms they manage. Using a unique data source that allows us to measure personal wealth and indebtness in great detail, we find a connection between CEOs' personal leverage and that of their firms. The connection is driven by the CEOs with a longer tenure and the CEOs who serve in a du

The 2010 population and housing census in Ghana revealed that more than half of the Ghanaian population lived in urban centers. Critical to the phenomenon of urbanization is the question of how to sustainably feed the urban population especially the urban poor as rapid urbanization has the tendency to urbanize poverty. This has led to renewed policy debate about the implications of farming in citi

National accounts suggest that the Common Pochard Aythya ferina was an uncommon breeding bird throughout western Europe before 1850. Extensions to the breeding range in the late 19th century were potentially aided by the rapid development of managed fish-ponds in eastern Europe, which provided suitable novel habitat at that time. Expansion into western Europe followed in subsequent decades. Wetlan

The central question addressed in this thesis is how to make the free-electron laser (FEL) more efficient. In recent years, coherent diffraction imaging provides an important motivation for efficiency enhancement. This is because a more efficient FEL process enables converting a larger fraction of the electron beam's power into optical power. By increasing the average optical power to the terawattThe central question addressed in this thesis is how to make the free-electron laser (FEL) more efficient. In recent years, coherent diffraction imaging provides an important motivation for efficiency enhancement. This is because a more efficient FEL process enables converting a larger fraction of the electron beam's power into optical power. By increasing the average optical power to the terawatt

We consider the Dirichlet-Neumann iteration for partitioned simulation of thermal fluid-structure interaction, also called conjugate heat transfer. We analyze its convergence rate for two coupled fully discretized 1D linear heat equations with jumps in the material coefficients across these. These are discretized using implicit Euler in time, a finite element method on one domain, a finite volume