Search results for "performance"

Contribution à l’étude des déterminants de la performance des firmes à forte intensité de connaissance

2022

Notre recherche est une contribution à la littérature sur la performance des firmes à forte intensité de connaissances à travers une proposition d’explication par des mécanismes organisationnels. Pour ce, nous avons combiné les apports de la théorie de l’architecture organisationnelle avec l’approche basée sur les ressources. A travers une étude de cas sur le secteur du conseil numérique en France, nous avons examiné l’impact d’une architecture organisationnelle cohérente et un actif cognitif sur la performance d’une entreprise de service numérique. Les résultats plaident en faveur d’une complémentarité d’explication de l’architecture organisationnelle et un actif organisationnel minutieuse…

Preparative separation of phospholipids by flash-HPLC

1988

Thermal performance and microclimate test methods for flat-plate solar thermal collectors

2012

In this Master’s thesis testing methods, experimental setups and data evaluation procedures for flat-plate solar thermal collectors are presented. An official quasi-dynamic test method according to the EU standard EN 12975 for evaluating the collector’s thermal performance is described, and its applicability to an existing experimental setup is evaluated. The general practicality of this setup is also reviewed. Furthermore, a second experimental setup is designed to monitor the inside conditions, or microclimate, of a solar thermal collector, in order to assess the frequency of condensation occurrence inside the collector. This work’s results include that the existing thermal performance se…

Simultaneous determination of four 5-hydroxy polymethoxyflavones by reversed-phase high performance liquid chromatography with electrochemical detect…

2009

Accumulating evidence has suggested the potential health-promoting effects of 5-hydroxy polymethoxyflavones (5-OH-PMFs) naturally existing in citrus genus. However, research efforts are hampered by the lack of reliable and sensitive methods for their determination in plant materials and biological samples. Using reversed-phase high performance liquid chromatography (HPLC) equipped with electrochemical (EC) detection, we have developed a fast and highly sensitive method for quantification of four 5-OH-PMFs, namely 5-hydroxy-6,7,8,3',4'-pentamethoxyflavone, 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone, 5-hydroxy-6,7,4'-trimethoxyflavone, and 5-hydroxy-6,7,8,4'-tetramethoxyflavone. The method wa…

Isolation and Characterization of Structurally Novel Antimutagenic Flavonoids from Spinach (Spinacia oleracea)

2001

Thirteen compounds, isolated from spinach (Spinacia oleracea), acted as antimutagens against the dietary carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline in Salmonella typhimurium TA 98. The antimutagens were purified by preparative and micropreparative HPLC from a methanol/water (70:30, v/v) extract of dry spinach (commercial product) after removal of lipophilic compounds such as chlorophylls and carotenoids by solid-phase extraction (SPE). Pure active compounds were identified by instrumental analysis including FT-IR, (1)H and (13)C NMR, UV-vis spectroscopy, and mass spectrometry. All of these compounds were flavonoids and related compounds that could be attributed to five groups: (A, m…

Supercritical fluid extraction and HPLC determination of relevant polyphenolic compounds in grape skin.

2005

The polyphenols determined are: (+)-catechin, (-)-epicatechin, rutin, quercetin and trans-resveratrol. Suitable conditions of supercritical fluid extraction were established using ethanol as a modifier of the polarity solvent (supercritical carbon dioxide). Final extraction conditions were: 20% v/v ethanol, 60degreesC, 250 bars and flow rate 2 mL/min. Static step time and dynamic step time were established using a selected grape skin sample. The extract was collected in water; the more polar polyphenols ((+)-catechin and (-)-epicatechin) remain in solution but rutin, quercetin and trans-resveratrol precipitate in this medium, thereby the solution of the extracted polyphenols was filtered. (…

Effectiveness of sodium acetate treatment on the mechanical properties and morphology of natural fiber-reinforced composites

2021

This paper aims to investigate the ability of an eco-friendly and cheap treatment based on sodium acetate solutions to improve the mechanical properties of flax fiber-reinforced composites. Flax fibers were treated for 5 days (i.e., 120 h) at 25 °C with mildly alkaline solutions at 5%, 10% and 20% weight content of the sodium salt. Quasi-static tensile and flexural tests, Charpy impact tests and dynamical mechanical thermal (DMTA) tests were carried out to evaluate the mechanical properties of the resulting composites. Fourier transform infrared analysis (FTIR) was used to evaluate the chemical modification on the fibers surface due to the proposed treatment, whereas scanning electron micro…

Influencias flamencas en la obra de Joan de Joanes

2016

Joan V. Macip, alias Joan de Joanes, fue sin lugar a dudas el renovador estilístico del taller dirigido por su padre, Vicent Macip, hasta al menos 1542, fecha en la que aparece como titular del mismo. En este contexto, con la culminación del retablo de Segorbe se inicia una etapa en la que el genio creativo de Joanes se manifiesta progresivamente con mayor nitidez, al combinar magistralmente en su producción artística los italianismos importados con los influjos flamencos presentes en la ciudad a través de Mencía de Mendoza,  culta noble y ardua coleccionista que vivió a caballo entre España y Flandes, especialmente en Valencia.

Network and System Performance Management for Next Generation Networks

2006

The physical and logical structures of next generation network and service environment is complex and requires increasingly sophisticated and complicated tools to be fully controllable and well managed. The main problem that has risen is that the old telemanagement model has not enough flexibility to manage rapidly and constantly changing network environment. 3G and 4G networks are basically IP based and the knowledge of IP type traffic management is somewhat new and challenging to telecom vendors. The present way of controlling and managing telecom systems is to use Non Real Time off-line PM (Performance Monitoring) and tools. Time periods between tuning can now be some days to some weeks …

A Review of Key Performance Indicators for Building Flexibility Quantification to Support the Clean Energy Transition

2021

The transition to a sustainable society and a carbon-neutral economy by 2050 requires extensive deployment of renewable energy sources that, due to the aleatority and non-programmability of most of them, may seriously affect the stability of existing power grids. In this context, buildings are increasingly being seen as a potential source of energy flexibility for the power grid. In literature, key performance indicators, allowing different aspects of the load management, are used to investigate buildings’ energy flexibility. The paper reviews existing indicators developed in the context of theoretical, experimental and numerical studies on flexible buildings, outlining the current status a…