Simplified Way (simplified + way)

Distribution by Scientific Domains


Selected Abstracts


CFD Sinflow Library: A framework to develop engineering educational codes in CFD and thermal sciences

COMPUTER APPLICATIONS IN ENGINEERING EDUCATION, Issue 1 2004
Romeu André Pieritz
Abstract This work introduces the educational code development library "CFD Sinflow Library" specialized in 2D numerical methods in computational fluid dynamics (CFD) and termal science. This library is for research, educational, and engineering purposes like an open and platform independent architecture. The library was developed with C++ standard programming language using an object-oriented approach allowing educators and graduation/undergraduation students to access the numerical methods in a simplified way. The numerical capabilities and results quality are evaluated, where comparisons are made with benchmark and analytical solutions. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 31,43, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10056 [source]


Two independent gene signatures in pediatric t(4;11) acute lymphoblastic leukemia patients

EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2009
Luca Trentin
Abstract Objective:, Gene expression profiles become increasingly more important for diagnostic procedures, allowing clinical predictions including treatment response and outcome. However, the establishment of specific and robust gene signatures from microarray data sets requires the analysis of large numbers of patients and the application of complex biostatistical algorithms. Especially in case of rare diseases and due to these constrains, diagnostic centers with limited access to patients or bioinformatic resources are excluded from implementing these new technologies. Method:, In our study we sought to overcome these limitations and for proof of principle, we analyzed the rare t(4;11) leukemia disease entity. First, gene expression data of each t(4;11) leukemia patient were normalized by pairwise subtraction against normal bone marrow (n = 3) to identify significantly deregulated gene sets for each patient. Result:, A ,core signature' of 186 commonly deregulated genes present in each investigated t(4;11) leukemia patient was defined. Linking the obtained gene sets to four biological discriminators (HOXA gene expression, age at diagnosis, fusion gene transcripts and chromosomal breakpoints) divided patients into two distinct subgroups: the first one comprised infant patients with low HOXA genes expression and the MLL breakpoints within introns 11/12. The second one comprised non-infant patients with high HOXA expression and MLL breakpoints within introns 9/10. Conclusion:, A yet homogeneous leukemia entity was further subdivided, based on distinct genetic properties. This approach provided a simplified way to obtain robust and disease-specific gene signatures even in smaller cohorts. [source]


Mathematical simulation of calcimine deliming in the production of gelatin

AICHE JOURNAL, Issue 7 2010
Karel Kolomazník
Abstract Calcimine is a valuable by-product originating during the processing of cured hide into leather. It is used as raw material in the production of gelatin and biodegradable sheets. For further usage, it is necessary to remove calcium hydroxide from calcimine by chemical deliming, which is, from the environmental protection point of view, the most important stage of the entire deliming process. In this article, a mathematical description of chemical deliming is proposed, based on the unreacted nucleus approach. Numerical solution of the model is found, concentration fields of the reacting chemicals described, and the evolution of the acido-basic boundary inside calcimine shown. The model is used to justify a simplified way to determine the effective diffusion coefficient of the deliming agent. The model can also be used as a basis for optimization of the deliming process. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source]


The Orbitrap: a new mass spectrometer

JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 4 2005
Qizhi Hu
Abstract Research areas such as proteomics and metabolomics are driving the demand for mass spectrometers that have high performance but modest power requirements, size, and cost. This paper describes such an instrument, the Orbitrap, based on a new type of mass analyzer invented by Makarov. The Orbitrap operates by radially trapping ions about a central spindle electrode. An outer barrel-like electrode is coaxial with the inner spindlelike electrode and mass/charge values are measured from the frequency of harmonic ion oscillations, along the axis of the electric field, undergone by the orbitally trapped ions. This axial frequency is independent of the energy and spatial spread of the ions. Ion frequencies are measured non-destructively by acquisition of time-domain image current transients, with subsequent fast Fourier transforms (FFTs) being used to obtain the mass spectra. In addition to describing the Orbitrap mass analyzer, this paper also describes a complete Orbitrap-based mass spectrometer, equipped with an electrospray ionization source (ESI). Ions are transferred from the ESI source through three stages of differential pumping using RF guide quadrupoles. The third quadrupole, pressurized to less than 10,3 Torr with collision gas, acts as an ion accumulator; ion/neutral collisions slow the ions and cause them to pool in an axial potential well at the end of the quadrupole. Ion bunches are injected from this pool into the Orbitrap analyzer for mass analysis. The ion injection process is described in a simplified way, including a description of electrodynamic squeezing, field compensation for the effects of the ion injection slit, and criteria for orbital stability. Features of the Orbitrap at its present stage of development include high mass resolution (up to 150 000), large space charge capacity, high mass accuracy (2,5 ppm), a mass/charge range of at least 6000, and dynamic range greater than 10.3 Applications based on electrospray ionization are described, including characterization of transition-metal complexes, oligosaccharides, peptides, and proteins. Use is also made of the high-resolution capabilities of the Orbitrap to confirm the presence of metaclusters of serine octamers in ESI mass spectra and to perform H/D exchange experiments on these ions in the storage quadrupole. Copyright © 2005 John Wiley & Sons, Ltd. [source]


Sweet nationalism in bitter days: a commercial representation of Zionism

NATIONS AND NATIONALISM, Issue 3 2009
ANAT FIRST
ABSTRACT. This article identifies several theoretical approaches to the role of culture in the construction of national identity. Embedded in the presently emerging approach, which emphasises the relations between popular culture/consumerism and national identity, this study focuses on a specific consumer good manufactured in Israel in the early 2000s, the height of the second Palestinian Intifada (uprising): small sugar packets bearing portraits of the patriarchs of Zionism. The analysis of this product, employing semiotic analysis, interviews and focus groups, locates it in the five ,moments' of du Gay's ,circuit of culture' (i.e. identity, representation, production, consumption and regulation). Three main general arguments were stated, empirically examined and largely sustained: (1) Consumer goods are used not only for constructing national identity but also as a means for ,healing' it; (2) in their ,healing' capacity, representations of nationalism on consumer goods do not add new elements to representations offered by the ,high' official version of nationalism but replicate them in a simplified way; (3) while trivialising the insights and concepts that originated in ,high' culture, consumer goods expose the prejudices, stereotypes and rules of inclusion and exclusion that in ,high' culture are often hidden in a sophisticated manner. [source]


Some numerical properties of approaches to physics,dynamics coupling for NWP

THE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 614 2006
Mark Dubal
Abstract At the present time there exist a number of different approaches to the problem of coupling parametrized physical processes to the dynamical core in operational numerical weather-prediction (NWP) and climate models. Motivated by the various strategies in use, some idealized representative coupling schemes are constructed and subsequently analysed using a methodology in which the physics and dynamics terms are represented in a simplified way. Particular numerical properties of the idealized schemes which are of interest are the ability to capture correct steady-state solutions and to be second-order accurate in time. In general, the schemes require specific choices for the time-differencing of certain coupled processes if correct steady-state solutions are to be obtained. This has implications for the overall numerical stability of a coupling strategy. An alternative physics,dynamics coupling approach is then described and analysed. A multiple-sweep predictor,corrector coupling scheme is shown to capture the correct steady-state solution and to allow for second-order accuracy, provided that the convective process is coupled explicitly. This approach has a number of advantages over those currently used in operational NWP models. Copyright © 2006 Crown copyright [source]


Vereinfachtes Flächenerfassungsmodell für Mehrzonenbilanzen

BAUPHYSIK, Issue 3 2009
Markus Lichtmeß Dipl.-Ing.
Berechnungsverfahren; Technische Regelwerke Abstract Bei der energetischen Bilanzierung nach DIN V 18599 müssen Gebäude aufgrund unterschiedlicher Nutzungseigenschaften zoniert werden. Auch die Gebäudehüllfläche wird nach diesen Kriterien aufgeteilt und den Zonen zur weiteren Berechnung zugewiesen. In der Praxis ist die Aufteilung der inneren Zonenumschließungs- und der äußeren Gebäudehüllfläche mit einem hohen Arbeitsaufwand verbunden. Etwa 50 % der Zeit wird für die Zonierung und die Ermittlung dieser Flächen- und Bauteileigenschaften benötigt. Zur Verringerung des Zeitaufwandes wurde eine Methode entwickelt, mit welcher die Gebäudehülle ähnlich dem 1-Zonen-Modell erfasst werden kann. Die Hüllfläche wird den Zonen vereinfacht zugeordnet, sodass die eigentliche Berechnung in der Mehrzonenbilanz erfolgen kann. Dies bringt wesentliche Vorteile bei der Auslegung und Optimierung nachgeschalteter Anlagentechnik mit sich. Die Verteilung der thermischen Hüllflächen erfolgt bei diesem vereinfachten Verfahren in Abhängigkeit von der Zonengröße und kann über ein Wichtungsverfahren beeinflusst bzw. korrigiert werden. Untersuchungen an mehreren Gebäuden haben gezeigt, dass die Flächenverteilung mit einer guten Genauigkeit eingesetzt werden kann, wobei eine "intelligente" Zuteilung über ein Wichtungsverfahren erforderlich ist. Die Zeitersparnis bei Anwendung der Vereinfachungen beträgt etwa 30 %. Bei komplexeren, vielzonigen Gebäuden ist die Einsparung tendenziell höher einzuschätzen. Das Verfahren erlaubt, alle Bauteilflächen detailliert auf Zonenebene nachzueditieren und somit die Möglichkeit, das Gebäudemodell planungsbegleitend zu konkretisieren. So kann die Berechnung im Laufe der Projektbearbeitung immer weiter präzisiert werden, wodurch die Berechnungsgenauigkeit und die Optimierungsmöglichkeiten gesteigert werden. Diese Vereinfachungen sollen zukünftig in der Luxemburger EnEV zur energetischen Bewertung von neu zu errichtenden Nichtwohngebäuden nach DIN V 18599 Anwendung finden. A simplified surface area calculation and zoning model for energy performance assessment of buildings. According to the DIN V 18599 energy performance assessment, buildings have to be divided into zones depending on their utilisation. The same zoning applies to the building envelope where the segments are being allocated to the individual zones. In engineering practice about 50% of the work is required for zoning, calculating surface areas and evaluating the properties of building envelope components. In order to reduce the time needed for these efforts a methodology similar to the single zone model has been developed. To carry out the multiple zone calculation the building envelope is being split and allocated to the individual zones in a simplified way. This as well provides a significant advantage for the dimensioning and optimisation of the related HVAC and lighting systems. Within the simplified calculation, the allocation of the building envelope is carried out in dependence of the zone size and corrected with a weighting factor if needed. The analysis of several buildings has shown that the simplified method can be applied with sufficient accuracy. The weighting factors are however necessary. By implementing this simplification the time expenditure to calculate a building is reduced by more or less 30%. This reduction tends to be even more important when dealing with complex buildings which have a high number of zones. The methodology enables building components to be edited by zones and hereby gives the opportunity to easily modify the design during the course of the planning. As the project develops, the calculations can be more detailed thereby increasing the precision of the calculation. In the near future this methodology will be implemented in the Luxembourg energy saving ordinance (EnEV) for the energy performance assessment of non residential buildings. [source]


Exploring complex interactions in designed data using GEMANOVA.

JOURNAL OF CHEMOMETRICS, Issue 6 2002
Color changes in fresh beef during storage
Abstract Data from a severely reduced experimental design are investigated in order to obtain detailed information on important factors affecting the changes in quality of meat during storage under different conditions. It is possible to model the response, meat color, using traditional ANOVA (analysis of variance) techniques, but the exploratory and explanatory value of this model is somewhat restricted owing to the number of factors and the fact that several interactions exist. For those reasons, it is not possible to visualize the model in a simple way and therefore not possible to have a clear overview of the total variation in the data. Using a recently suggested alternative to traditional analysis of variance, GEMANOVA (generalized multiplicative ANOVA), it is possible to analyze the data effectively and obtain a more interpretable solution that enables a simple overview of the whole sampling domain. Whereas traditional analysis of variance typically seeks a model with main effects and as few and simple interactions and cross-products as possible, the GEMANOVA model seeks to describe the data primarily by means of higher-order interactions, albeit in a straightforward way. The two approaches are thus complementary. It is shown that the GEMANOVA model is simple to interpret, primarily because the GEMANOVA structure is in agreement with the nature of the data. It is shown that the GEMANOVA model used is mathematically unique, which leads to attractive simplified ways of interpreting the model. The results presented are the first published results where the GEMANOVA model is not simply equivalent to an ordinary PARAFAC model, thus taking full advantage of the additional structural power of GEMANOVA. A new algorithm for fitting the GEMANOVA model is developed and is available from the authors. Copyright © 2002 John Wiley & Sons, Ltd. [source]