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排序方式: 共有336条查询结果,搜索用时 15 毫秒
1.
Aard J. Groen Petra C. De WeerdNederhof Inge C. Kerssensvan Drongelen Rob A.J. Badoux Gerard P.H. Olthuis 《Creativity & Innovation Management》2002,11(1):2-16
In this paper we describe a framework for analysing the creation and justification of Research & Development. The 4S framework is developed for analysing the scope, scale, skills and social network aspects of Research & Development value. The framework is based on social system theory, a process contingency model, and recent Research & Development metrics. We present a first empirical assessment based on a workshop using the 4S framework for leveraging Research & Development. Results that assist in the assessment of value creation utilising R & D within networks are very relevant in high tech industries. The multi–dimensional process approach of this framework seems promising for understanding and managing R&D value creation, but needs further operationalisation. Case studies are described and a Dutch network on leveraging R&D has been initiated. 相似文献
2.
Huong Thi Le Inge D Brouwer Jan Burema Khan Cong Nguyen Frans J Kok 《Nutrition journal》2006,5(1):1-8
Background
Parents of six children are facing a trial on charges of aggravated manslaughter in the care a 5 1/2 month old infant who died suddenly and neglect of their four older children for causing them to be malnourished by feeding them all an exclusively raw foods vegan diet. Both parents declined plea bargains and plan to defend themselves in court. 相似文献3.
Simon Stisen Inge Sandholt Anette Nørgaard Rasmus Fensholt Karsten Høgh Jensen 《Remote sensing of environment》2008,112(3):1242-1255
Spatially distributed estimates of evaporative fraction and actual evapotranspiration are pursued using a simple remote sensing technique based on a remotely sensed vegetation index (NDVI) and diurnal changes in land surface temperature. The technique, known as the triangle method, is improved by utilizing the high temporal resolution of the geostationary MSG-SEVIRI sensor. With 15 min acquisition intervals, the MSG-SEVIRI data allow for a precise estimation of the morning rise in land surface temperature which is a strong proxy for total daytime sensible heat fluxes. Combining the diurnal change in surface temperature, dTs with an interpretation of the triangular shaped dTs − NDVI space allows for a direct estimation of evaporative fraction. The mean daytime energy available for evapotranspiration (Rn − G) is estimated using several remote sensors and limited ancillary data. Finally regional estimates of actual evapotranspiration are made by combining evaporative fraction and available energy estimates. The estimated evaporative fraction (EF) and actual evapotranspiration (ET) for the Senegal River basin have been validated against field observations for the rainy season 2005. The validation results showed low biases and RMSE and R2 of 0.13 [−] and 0.63 for EF and RMSE of 41.45 W m− 2 and R2 of 0.66 for ET. 相似文献
4.
Simon Richard Proud Mads Olander Rasmussen Inge Sandholt Wycliffe Mutero Assaf Anyamba 《Remote sensing of environment》2010,114(8):1687-1698
In order to obtain high quality data, the correction of atmospheric perturbations acting upon land surface reflectance measurements recorded by a space-based sensor is an important topic within remote sensing. For many years the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) radiative transfer model and the Simplified Method for Atmospheric Correction (SMAC) codes have been used for this atmospheric correction, but previous studies have shown that in a number of situations the quality of correction provided by the SMAC is low. This paper describes a method designed to improve the quality of the SMAC atmospheric correction algorithm through a slight increase in its computational complexity. Data gathered from the SEVIRI aboard Meteosat Second Generation (MSG) is used to validate the additions to SMAC, both by comparison to simulated data corrected using the highly accurate 6S method and by comparison to in-situ and 6S corrected SEVIRI data gathered for two field sites in Africa. The additions to the SMAC are found to greatly increase the quality of atmospheric correction performed, as well as broaden the range of atmospheric conditions under which the SMAC can be applied. When examining the Normalised Difference Vegetation Index (NDVI), the relative difference between SMAC and in-situ values decreases by 1.5% with the improvements in place. Similarly, the mean relative difference between SMAC and 6S reflectance values decreases by a mean of 13, 14.5 and 8.5% for Channels 1, 2 and 3 respectively. Furthermore, the processing speed of the SMAC is found to remain largely unaffected, with only a small increase in the time taken to process a full SEVIRI scene. Whilst the method described within this paper is only applicable to SEVIRI data, a similar approach can be applied to other data sources than SEVIRI, and should result in a similar accuracy improvement no matter which instrument supplies the original data. 相似文献
5.
Inge van de Weerd Sjaak Brinkkemper Johan Versendaal 《Information and Software Technology》2010,52(7):720-732
Company growth in a global setting causes challenges in the adaptation and maintenance of an organization’s methods. In this paper, we will analyze incremental method evolution in software product management in a global environment. We validate a method increment approach, based on method engineering principles, by applying it to a retrospective case study conducted at a large ERP vendor. The results show that the method increment types cover all increments that were found in the case study. Also, we identified the following lessons learned for company growth in a global software product management context: method increment drivers, such as the change of business strategy, vary during evolution; a shared infrastructure is critical for rollout; small increments facilitate gradual process improvement; and global involvement is critical. We then claim that method increments enable software companies to accommodate evolutionary adaptations of development process in agreement with the overall company expansion. 相似文献
6.
Air temperature estimation with MSG-SEVIRI data: Calibration and validation of the TVX algorithm for the Iberian Peninsula 总被引:3,自引:0,他引:3
Air temperature can be estimated from remote sensing by combining information in thermal infrared and optical wavelengths. The empirical TVX algorithm is based on an estimated linear relationship between observed Land Surface Temperature (LST) and a Spectral Vegetation Index (NDVI). Air temperature is assumed to be equal to the LST corresponding to the effective full vegetation cover, and is found by extrapolating the line to a maximum value of NDVImax. The algorithm has been tested and reported in the literature previously. However, the effect of vegetation types and climates and the potential variation in NDVI of the effective full cover has not been subject for investigation. The present study proposes a novel methodology to estimate NDVImax that uses observed air temperature to calibrate the NDVImax for each vegetation type. To assess the validity of this methodology, we have compared the accuracy of estimates using the new NDVImax and the previous NDVImax that have been proposed in literature with MSG-SEVIRI images in Spain during the year 2005. In addition, a spatio-temporal assessment of residuals has been performed to evaluate the accuracy of retrievals in terms of daily and seasonal variation, land cover, landscape heterogeneity and topography. Results showed that the new calibrated NDVImax perform well, with a Mean Absolute Error ranging between 2.8 °C and 4 °C. In addition, vegetation-specific NDVImax improve the accuracy compared with a unique NDVImax. 相似文献
7.
Inge de Wreede und Hermann Stegemann 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1982,174(3):200-207
Zusammenfassung Die fraktionierte Extraktion mit Na-dodecylsulfat(SDS)-Lösungen ermöglicht die Trennung von Muskel- und Bindegewebs-Protein. In einem zweiten Schritt kann auch Kollagen von Elastin getrennt werden. Muskelprotein löst sich unter Schütteln bei Zimmertemperatur in einer SDS(2%)-ME(1%)-Lösung in einem Boratpuffer pH 9. Zur Lösung des Kollagens sind 100°C, intensives Rühren und eine SDS(8%)-ME(1%)-Lösung in einem Citratpuffer pH 5 notwendig. Das Verfahren wurde an nativem und hitzedenaturiertem Material angewendet. Die Möglichkeit zur Bestimmung des BEFFE-Wertes in Brühwürsten mit dieser Methode wird untersucht und die Anwendung auf andere Fleischprodukte diskutiert.
Benutzte Abkürzungen NPN Nichteiweißstickstoffverbindungen - ATM Acetontrockenmasse - BEFFE bindegewebseiweißfreies Fleischeiweiß - OH-Pro Hydroxyprolin - SDS Natrium(Sodium)-dodecylsulfat - ME 2-Mercapto-äthanol - Tris Tris-(hydroxymethyl)aminomethan - PAGE Polyacrylamid-Gelelektrophorese - Vk Variationskoeffizient - S Standardabweichung - Mittelwert Die Arbeit ist Teil der Dissertation von I. de WreedeWir danken der Deutschen Forschungsgemeinschaft für ihre finanzielle Unterstützung und Herrn Dr. H. H. Heinert, Leiter des Staatl. Veterinär-Untersuchungsamtes Braunschweig, der freundlicherweise die Brühwurstproben zur Verfügung gestellt hat 相似文献
Fractionation of muscle protein, collagen and elastin by extraction with buffers containing dodecylsulfat (SDS)
Summary Dodecylsulfate (SDS) containing buffers were used for stepwise extraction of proteins from muscle and connective tissue. The first step was done at room temperature with borate buffer pH 9 and the muscle proteins were extracted. The second treatment (citrate buffer pH 5 at 100°C) dissolved collagen and left elastin as residue. All extracts were analysed by electrophoresis to identify the proteins and evaluated by a biuret method insensitive to SDS and ME. This method was applied to native and heatdenatured proteins and to Brühwdrste. The possibility of applying this method to the determination of the BEFFE-content is discussed.
Benutzte Abkürzungen NPN Nichteiweißstickstoffverbindungen - ATM Acetontrockenmasse - BEFFE bindegewebseiweißfreies Fleischeiweiß - OH-Pro Hydroxyprolin - SDS Natrium(Sodium)-dodecylsulfat - ME 2-Mercapto-äthanol - Tris Tris-(hydroxymethyl)aminomethan - PAGE Polyacrylamid-Gelelektrophorese - Vk Variationskoeffizient - S Standardabweichung - Mittelwert Die Arbeit ist Teil der Dissertation von I. de WreedeWir danken der Deutschen Forschungsgemeinschaft für ihre finanzielle Unterstützung und Herrn Dr. H. H. Heinert, Leiter des Staatl. Veterinär-Untersuchungsamtes Braunschweig, der freundlicherweise die Brühwurstproben zur Verfügung gestellt hat 相似文献
8.
Genetic Dissection of Light-Regulated Adventitious Root Induction in Arabidopsis thaliana Hypocotyls
Yinwei Zeng Sebastien Schotte Hoang Khai Trinh Inge Verstraeten Jing Li Ellen Van de Velde Steffen Vanneste Danny Geelen 《International journal of molecular sciences》2022,23(10)
Photomorphogenic responses of etiolated seedlings include the inhibition of hypocotyl elongation and opening of the apical hook. In addition, dark-grown seedlings respond to light by the formation of adventitious roots (AR) on the hypocotyl. How light signaling controls adventitious rooting is less well understood. Hereto, we analyzed adventitious rooting under different light conditions in wild type and photomorphogenesis mutants in Arabidopsis thaliana. Etiolation was not essential for AR formation but raised the competence to form AR under white and blue light. The blue light receptors CRY1 and PHOT1/PHOT2 are key elements contributing to the induction of AR formation in response to light. Furthermore, etiolation-controlled competence for AR formation depended on the COP9 signalosome, E3 ubiquitin ligase CONSTITUTIVELY PHOTOMORPHOGENIC (COP1), the COP1 interacting SUPPRESSOR OF PHYA-105 (SPA) kinase family members (SPA1,2 and 3) and Phytochrome-Interacting Factors (PIF). In contrast, ELONGATED HYPOCOTYL5 (HY5), suppressed AR formation. These findings provide a genetic framework that explains the high and low AR competence of Arabidopsis thaliana hypocotyls that were treated with dark, and light, respectively. We propose that light-induced auxin signal dissipation generates a transient auxin maximum that explains AR induction by a dark to light switch. 相似文献
9.
10.
Bellemans Inge De Wilde Evelien Blanpain Bart Moelans Nele Verbeken Kim 《Metallurgical and Materials Transactions B》2017,48(6):3058-3073
Metallurgical and Materials Transactions B - This study investigates the origin of mechanically entrained metal droplets in liquid slag due to their interaction with solid spinel particles. Two... 相似文献