Search results for "FREQUENCY"

Line shape measurements of rubidium 5S-7S two-photon transition

2014

We report the use of a digital lock to measure the line profile and center frequency of rubidium 5S-7S two-photon transitions with a cw laser referenced to an optical frequency comb. The narrow, two-photon transition, 5S-7S (760 nm), insensitive to first-order in a magnetic field, is a promising candidate for frequency reference.

The second century CE Roman watermills of Barbegal Unraveling the enigma of one of the oldest industrial complexes

2018

Carbonate deposits provide insights into the operation of the earliest industrial utilization of hydropower by an ancient society.

Homozygous familial hypercholesterolaemia: new insights and guidance for clinicians to improve detection and clinical management. A position paper fr…

2014

Item does not contain fulltext AIMS: Homozygous familial hypercholesterolaemia (HoFH) is a rare life-threatening condition characterized by markedly elevated circulating levels of low-density lipoprotein cholesterol (LDL-C) and accelerated, premature atherosclerotic cardiovascular disease (ACVD). Given recent insights into the heterogeneity of genetic defects and clinical phenotype of HoFH, and the availability of new therapeutic options, this Consensus Panel on Familial Hypercholesterolaemia of the European Atherosclerosis Society (EAS) critically reviewed available data with the aim of providing clinical guidance for the recognition and management of HoFH. METHODS AND RESULTS: Early diagn…

Evaluation of the Sensory Profiles of Texas High Plains Tempranillo and Cabernet Sauvignon Wines

2017

A trained panel was asked to evaluate the sensory profiles of Tempranillo and Cabernet Sauvignon varietal wines from the Texas High Plains American Viticultural Area. The panelists evaluated 20 different wines using a modified conventional descriptive analysis and a modified citation frequency-based method. Our study revealed a significant correlation between both methods in the distribution of wines. The two varietal wines could not be significantly distinguished by their average sensory profiles, although butter, caramel and lavender were significantly stronger in Tempranillo and black currant in Cabernet Sauvignon. Both average sensory profiles were mainly driven by their oak-related cha…

Lead-Lag-Shaped Interactive Force Estimation by Equivalent Output Injection of Sliding-Mode

2020

Estimation of interactive forces, which are mostly unavailable for direct measurement on the interface between a system and its environment, is an essential task in various motion control applications. This paper proposes an interactive force estimation method, based on the well-known equivalent output injection of the second-order sliding mode. The equivalent output injection is used to obtain a frequency-unshaped quantity that appears as a matched external disturbance and encompasses the interactive forces. Afterwards, a universal lead-lag shaper, depending on dynamics of the motion control system coupled with its environment, is used to extract an interactive force quantity. Once identif…

Anharmonicity modeling in hydrogen bonded solvent dimers

2021

Abstract Harmonic and anharmonic frequencies of dimers and mixed dimers of water, methanol and benzene were computed and the results were critically analysed to investigate the anharmonicity of the normal mode vibrations within density functional theory (DFT) with empirically included Grimme correction for dispersion (D3). From several options, the B3LYP-D3/6-31++G* level of theory was selected as a good compromise between accuracy and calculation speed, suitable for future modeling of larger solvent clusters. The obtained raw harmonic and anharmonic second-order perturbation theory of vibrational frequencies (VPT2) were additionally scaled using a two-range procedure (below and above 2000 …

Physical and hydraulic characterization of a clay soil at the plot scale

2010

Summary The soil physical and hydraulic properties have to be determined for interpreting and simulating many hydrological processes. An investigation was carried out to determine the physical and hydraulic characteristics of a clay soil at the plot scale. An intensive sampling of the surface soil layer of two plots of 4 × 11 m2 was carried out by measuring, for each plot, dry soil bulk density, ρb, and antecedent soil water content, θi, at 88 sampling points and field-saturated soil hydraulic conductivity, Kfs, at 176 sampling points. A wide range of Kfs values (0.7–5107 mm h−1) were measured by the Simplified Falling Head (SFH) technique. For each variable, the two plots yielded very simi…

The weight of the flood‐of‐record in flood frequency analysis

2018

Use of L-moments approach for regional flood frequency analysis in Sicily, Italy

2008

Extremely great floods are among environmental events with the most disastrous consequences for the entire world. Estimates of their return periods and design values are of great importance in hydrologic modeling, engineering practice for water resources and reservoirs design and management, planning for weather-related emergencies, etc. Regional flood frequency analysis resolves the problem of estimating the extreme flood events for catchments having short data records or ungauged catchments. This paper analyzes annual maximum peak flood discharge data recorded from more than 50 stream flow gauging sites in Sicily, Italy, in order to derive regional flood frequency curves. First these data…

Derivation of flood frequency curves in poorly gauged Mediterranean catchments using a simple stochastic hydrological rainfall-runoff model

2007

In this paper a Monte Carlo procedure for deriving frequency distributions of peak flows using a semi-distributed stochastic rainfall-runoff model is presented. The rainfall-runoff model here used is very simple one, with a limited number of parameters and practically does not require any calibration, resulting in a robust tool for those catchments which are partially or poorly gauged. The procedure is based on three modules: a stochastic rainfall generator module, a hydrologic loss module and a flood routing module. In the rainfall generator module the rainfall storm, i.e. the maximum rainfall depth for a fixed duration, is assumed to follow the two components extreme value (TCEV) distribu…