8,158 research outputs found
Cone Monotonicity: Structure Theorem, Properties, and Comparisons to Other Notions of Monotonicity
In search of a meaningful 2-dimensional analog to mono- tonicity, we
introduce two new definitions and give examples of and dis- cuss the
relationship between these definitions and others that we found in the
literature. Note: After we published the article in Abstract and Applied
Analysis and after we searched multiple times for previous work, we discovered
that Clarke at al. had introduced the definition of cone monotonicity and given
a characterization. See the addendum at the end of this paper for full
reference information
A Study of Conflict in Top Management Decision Making: The Impact of Contribution Motive
Decisions made by top management teams and the setting of goals for the organization are of critical importance. It seems likely the process is one that could be subject to conflict. This paper looks at conflict\u27s impact on firm behavior and a new approach for understanding conflict. The paper examines a study done by Amason and Sapienza, which tests a model that looks at the effects of two types of conflict and how the moderating variables they propose can impact the quality of decision-making. The article proposes a model that identifies an additional construct that, when added to their model, more fully specifies the impact of conflict on decision-making
Non-singular Ekpyrotic/Cyclic model in Loop Quantum Cosmology
We study the role of non-perturbative quantum gravity effects in the
Ekpyrotic/Cyclic model using the effective framework of loop quantum cosmology
in the presence of anisotropies. We show that quantum geometric modifications
to the dynamical equations near the Planck scale as understood in the
quantization of Bianchi-I spacetime in loop quantum cosmology lead to the
resolution of classical singularity and result in a non-singular transition of
the universe from the contracting to the expanding branch. In the Planck
regime, the universe undergoes multiple small bounces and the anisotropic shear
remains bounded throughout the evolution. A novel feature, which is absent for
isotropic models, is a natural turn around of the moduli field from the
negative region of the potential leading to a cyclic phenomena as envisioned in
the original paradigm. Our work suggests that incorporation of quantum
gravitational effects in the Ekpyrotic/Cyclic model may lead to a viable
scenario without any violation of the null energy condition.Comment: 24 pages, 11 figures. Additional numerical results discussed to show
robustness of non-singular bounce of the scale factor and turn-around of the
moduli field. References added. To appear in Physical Review
Apparent diffusivity model for concrete containing supplementary cementitious materials
Concrete’s resistance to chloride diffusion is one of the primary factors governing the concrete structure service life and life-cycle costs. This paper presents a new model developed for estimating the apparent concrete diffusivity based on the mixture proportions, cementitious materials used, and concrete age. The model includes the effects of supplementary cementitious material types commonly found in other service life models such as fly ash, ground-granulated blast-furnace slag, and silica fume. Also included are ultra-fine fly ash and metakaolin, which were not available in previous service life models. For validation of the model, chloride profiles have been measured on concrete blocks exposed daily to seawater for 25 years at the Treat Island, ME concrete exposure site. Concrete mixtures tested as part of the validation dataset contained up to 80% ground-granulated blast-furnace slag, 25% fly ash, or 20% silica fume, and were compared against the predicted values and are presented in this paper
Using presence-absence data to establish reserve selection procedures that are robust to temporal species turnover
Previous studies suggest that a network of nature reserves with maximum efficiency (obtained by selecting the minimum area such that each species is represented once) is likely to be insufficient to maintain species in the network over time. Here, we test the performance of three selection strategies which require presence-absence data, two of them previously proposed (multiple representations and selecting an increasing percentage of each species' range) and a novel one based on selecting the site where each species has exhibited a higher permanence rate in the past. Multiple representations appear to be a safer strategy than selecting a percentage of range because the former gives priority to rarer species while the latter favours the most widespread.
The most effective strategy was the one based on the permanence rate, indicating that the robustness of reserve networks can be improved by adopting reserve selection procedures that integrate information about the relative value of sites. This strategy was also very efficient, suggesting that the investment made in the monitoring schemes may be compensated for by a lower cost in reserve acquisition
Quantum non-demolition measurements of single donor spins in semiconductors
We propose a technique for measuring the state of a single donor electron
spin using a field-effect transistor induced two-dimensional electron gas and
electrically detected magnetic resonance techniques. The scheme is facilitated
by hyperfine coupling to the donor nucleus. We analyze the potential
sensitivity and outline experimental requirements. Our measurement provides a
single-shot, projective, and quantum non-demolition measurement of an
electron-encoded qubit state.Comment: 8+ pages. 4 figures. Published versio
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