Search results for " Methods"
showing 10 items of 4102 documents
Extraction Methods of Essential Oils From Herbs and Spices
2017
International audience; This chapter describes both conventional and non‐conventional extraction methods of essential oils (EOs) from herbs and spices. Although hydrodistillation, steam distillation and solvent extraction are the most applied methods, several non‐conventional technologies have been evaluated, especially in respect to EO recovery, and a great potential has been attributed to these non‐conventional methods. For instance, ultrasound, microwave, supercritical fluid, pulsed electric fields, ohmic‐heating and microwave (MW) extraction techniques applied alone or combined with other techniques are potent tools to obtain EOs in a 'green' way from natural resources such as aromatic …
Analysis of the determinants of entrepreneurial intention: the case of Burkina Faso
2018
International audience; In this study, we propose to analyze students' entrepreneurial intention, drawing on Lazear's (2004) self-selection model. This model captures the role of "human capital" in employment assignment and emphasizes the importance of the variety of skills in the individual's entrepreneurial orientation. For this purpose, we have a database collected in 2017 from over 1000 students at Ouaga I and Ouaga II universities in Burkina Faso. The results of estimates obtained using the quantile regression method show a positive and significant effect of the diversity of skills on the intention score, mainly at the median level. Even if the effect is not strong, this result support…
Enhancing Metastability by Dissipation and Driving in an Asymmetric Bistable Quantum System.
2018
The stabilizing effect of quantum fluctuations on the escape process and the relaxation dynamics from a quantum metastable state are investigated. Specifically, the quantum dynamics of a multilevel bistable system coupled to a bosonic Ohmic thermal bath in strong dissipation regime is analyzed. The study is performed by a non-perturbative method based on the real-time path integral approach of the Feynman-Vernon influence functional. We consider a strongly asymmetric double well potential with and without a monochromatic external driving, and with an out-of-equilibrium initial condition. In the absence of driving we observe a nonmonotonic behavior of the escape time from the metastable regi…
Numerical treatment of radiation processes in the internal shocks of magnetized relativistic outflows
2017
Los blázares son un tipo de núcleo activo de galaxia (AGN, por sus siglas en inglés) que se encuentran entre los objetos astrofísicos más energéticos y violentos, a la par de los brotes de rayos gamma (GRB por sus siglas en inglés). Los procesos físicos y, en particular, el escenario del chorro relativista en el que se genera la radiación ultraenergética detectada por observatorios terrestres y en órbita, han conseguido atraer la atención e interés de los astrónomos y astrofísicos desde su descubrimiento. En la presente tesis investigamos el modelo de choques internos (IS) cuya hipótesis consta del choque de dos capas de plasma con geometría cilíndrica, formando dos ondas de choque que atra…
Planning as evolution: radical pedagogy, creative methods and urban research
2022
Beyond reductionist thought, looking at a theoretical framework that embrace a complex dimension of knowledge, the urban planning discipline is going through a radical change. An attitude well expressed by a large group of intellectuals who recognize the fragility of the discipline and re-think themselves in opposition to the excess of specialization of the modern world to grasp the vital interconnection between things, the intersection spaces, on disciplinary boundaries, where concepts become images, symbols, practices, processes. In this ongoing change of paradigm, sensitive approaches and aesthetic rationalities arouse interest within urban and territorial studies. Starting from the inte…
Determinants of current account balances
2011
ENSEMBLE METHODS FOR RANKING DATA
2017
The last years have seen a remarkable flowering of works about the use of decision trees for ranking data. As a matter of fact, decision trees are useful and intuitive, but they are very unstable: small perturbations bring big changes. This is the reason why it could be necessary to use more stable procedures, as ensemble methods, in order to find which predictors are able to explain the preference structure. In this work ensemble methods as BAGGING and Random Forest are proposed, from both a theoretical and computational point of view, for deriving classification trees when ranking data are observed. The advantages of these procedures are shown through an example on the SUSHI data set.
Iodine(I) and Silver(I) Complexes Incorporating 3-Substituted Pyridines
2023
Building upon the first report of a 3-acetaminopyridine-based iodine(I) complex (1b) and its unexpected reactivity toward tBuOMe, several new 3-substituted iodine(I) complexes (2b–5b) have been synthesized. The iodine(I) complexes were synthesized from their analogous silver(I) complexes (2a–5a) via a silver(I) to iodine(I) cation exchange reaction, incorporating functionally related substituents as 3-acetaminopyridine in 1b; 3-acetylpyridine (3-Acpy; 2), 3-aminopyridine (3-NH2py; 3), and 3-dimethylaminopyridine (3-NMe2py; 4), as well as the strongly electron-withdrawing 3-cyanopyridine (3-CNpy; 5), to probe the possible limitations of iodine(I) complex formation. The individual properties …
Innovative sequential batch reactor solutions for wastewater treatment
2019
Sekwencyjne biologiczne reaktory (SBR) są szeroko wykorzystywane do oczyszczania ścieków, które obecnie stają się zanieczyszczone coraz to nowymi i bardziej złożonymi substancjami. Korzystne zatem staje się włączenie różnego rodzaju rozszerzających się konfiguracji oraz modyfikacji operacyjnych, aby efektywniej oczyszczać ścieki. W pracy przedstawiono podstawowy opis procesu SBR oraz jego modyfikacji, które prowadzą do lepszego usuwania powstających zanieczyszczeń. Scharakteryzowano cykliczny system osadów czynnych (CASS), który jest jednym z najpopularniejszych procesów reaktorów sekwencyjnych (SBR) stosowanych do oczyszczania ścieków komunalnych oraz ścieków z różnych branż, w tym rafiner…
The SO2F2 quasi-spherical top: Correspondence between tensorial and Watson's formalisms
2006
Abstract The SO2F2 quasi-spherical top molecule with C2v symmetry is considered as a distorted spherical top deriving from the SO 4 2 − tetrahedral ion. We present here a detailed correspondence between the tensorial formalism using the Td⊃C2v reorientation and the usual Hamiltonian of Watson. We have also performed ab initio calculations in order to determine the centrifugal distorsion constants in the vibrational ground state.