460 research outputs found
The Foundation of Pattern Structures and their Applications
This thesis is divided into a theoretical part, aimed at developing statements around the newly introduced concept of pattern morphisms, and a practical part, where we present use cases of pattern structures.
A first insight of our work clarifies the facts on projections of pattern structures. We discovered that a projection of a pattern structure does not always lead again to a pattern structure.
A solution to this problem, and one of the most important points of this thesis, is the introduction of pattern morphisms in Chapter4. Pattern morphisms make it possible to describe relationships between pattern structures, and thus enable a deeper understanding of pattern structures in general. They also provide the means to describe projections of pattern structures that lead to pattern structures again. In Chapter5 and Chapter6, we looked at the impact of morphisms between pattern structures on concept lattices and on their representations and thus clarified the theoretical background of existing research in this field.
The application part reveals that random forests can be described through pattern structures, which constitutes another central achievement of our work.
In order to demonstrate the practical relevance of our findings, we included a use case where this finding is used to build an algorithm that solves a real world classification problem of red wines. The prediction accuracy of the random forest is better, but the high interpretability makes our algorithm valuable.
Another approach to the red wine classification problem is presented in Chapter 8, where, starting from an elementary pattern structure, we built a classification model that yielded good results
German emigration via Bremen in the Weimar Republic (1920-1932)
This paper analyzes the oversea emigration of German passengers via the port of Bremen in the period of the Weimar Republic (1920–1932). We use a novel micro-dataset of digitalized passengers lists including about 181,000 emigrants as an estimation of the outflow of Germans from the German Reich. The descriptive analysis shows that the dataset is overall representative compared to official statistics except for the years 1924 and 1929 in which the data loss is huge. Furthermore, we deduce the skill level of the emigrating working population on the basis of information about occupations in the dataset. We find that male migrants had higher skills than female migrants and that South American countries attracted a relatively better skill distribution than the United States although the latter represented the main destination country for emigrants of any skill level in absolute numbers
Tests of quantitative precipitation estimates using national weather service dual-polarization radar in Missouri
Flash flooding is the most common and widespread threat associated with severe weather. Therefore, it is essential for forecasters to be able to properly assess the risk of flash flooding in order to issue watches and warnings. The underestimation of rainfall accumulation by radar algorithms often leads to undiagnosed flash flooding, so it is necessary to determine which type of quantitative precipitation estimation (QPE) equation best assesses the actual amount of rain that has fallen at a given location (Ryzhkov et al. 2005). By comparing the radar estimated rainfall to the accumulated precipitation measured by rain gauges, the bias and error of the QPE algorithms can be assessed. In the following study, these measurements will be compared for significant rainfall events that occurred across the state of Missouri in 2014. The data from twelve individual rain gauge sites, which are considered to provide the "ground truth" rainfall quantities (Kitchen and Blackall, 1992), are measured against the estimated rainfall calculated by the three National Weather Service radars. Also included is an analysis of whether gauge distance from the radar location has an effect on the error and bias. Various quality control (QC) methods are applied to the radar parameters in order to determine whether or not they enhance the outcomes of the statistical testing applied to the radar data. The results show that R(Z, ZDR) type equations produce the best data, as they give error and bias calculations closest to zero
Formal aspects of component software (FACS 2010 selected and extended papers)
This issue includes extended versions of selected best papers from the 7th International Workshop on Formal Aspects of Component Software (FACS 2010) held in Guimarães, Portugal on October 14–16, 2010. The component-based software development approach has emerged as a promising paradigm to cope with an ever increasing complexity of present-day software solutions by bringing sound production and engineering principles into software
engineering. However, many conceptual and technological issues remain that challenge component-based software development theory and practice. To address these issues, FACS seeks to provide a forum for researchers and practitioners in the areas of component software and formal methods to foster a better understanding of the component-based paradigm and its applications as well as how formal methods can or should be used to make component-based software development succeed
The Nature of Student Science Projects in Comparison to Educational Goals for Science
Author Institution: St. Francis de Sales High School ; Department of Curriculum & Instruction, Southern Illinois UniversityThe objective of this research was to determine if student science projects in Ohio were meeting educational goals for science as recommended by the American Association for the Advancement of Science, the National Science Teachers Association, and the Ohio Department of Education. In addition, five methods were examined to determine if each had a positive effect on science projects in meeting these educational goals. Teachers from the Diocese of Toledo with students completing science projects in The Ohio Academy of Science's District 2 were asked to rate projects for each aspect of eight educational goals for science defined by this study. Science projects were rated overwhelmingly and consistently positive on each goal. Modeling of skills in the classroom was found to be significantly linked to six of the eight goals for science education. In addition, there was evidence to suggest that participating at a district science fair and supportive help also improved these ratings
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Making limb and nadir measurements comparable: A common volume study of PMC brightness observed by Odin OSIRIS and AIM CIPS
Combining limb and nadir satellite observations of Polar Mesospheric Clouds (PMCs) has long been recognized as problematic due to differences in observation geometry, scattering conditions, and retrieval approaches. This study offers a method of comparing PMC brightness observations from the nadir-viewing Aeronomy of Ice in the Mesosphere (AIM) Cloud Imaging and Particle Size (CIPS) instrument and the limb-viewing Odin Optical Spectrograph and InfraRed Imaging System (OSIRIS). OSIRIS and CIPS measurements are made comparable by defining a common volume for overlapping OSIRIS and CIPS observations for two northern hemisphere (NH) PMC seasons: NH08 and NH09. We define a scattering intensity quantity that is suitable for either nadir or limb observations and for different scattering conditions. A known CIPS bias is applied, differences in instrument sensitivity are analyzed and taken into account, and effects of cloud inhomogeneity and common volume definition on the comparison are discussed. Not accounting for instrument sensitivity differences or inhomogeneities in the PMC field, the mean relative difference in cloud brightness (CIPS - OSIRIS) is −102 ± 55%. The differences are largest for coincidences with very inhomogeneous clouds that are dominated by pixels that CIPS reports as non-cloud points. Removing these coincidences, the mean relative difference in cloud brightness reduces to −6 ± 14%. The correlation coefficient between the CIPS and OSIRIS measurements of PMC brightness variations in space and time is remarkably high, at 0.94. Overall, the comparison shows excellent agreement despite different retrieval approaches and observation geometries
Pyrroloquinoline Quinone Aza-Crown Ether Complexes as Biomimetics for Lanthanide and Calcium Dependent Alcohol Dehydrogenases**
Understanding the role of metal ions in biology can lead to the development of new catalysts for several industrially important transformations. Lanthanides are the most recent group of metal ions that have been shown to be important in biology, that is, in quinone-dependent methanol dehydrogenases (MDH). Here we evaluate a literature-known pyrroloquinoline quinone (PQQ) and 1-aza-15-crown-5 based ligand platform as scaffold for Ca, Ba, La and Lu biomimetics of MDH and we evaluate the importance of ligand design, charge, size, counterions and base for the alcohol oxidation reaction using NMR spectroscopy. In addition, we report a new straightforward synthetic route (3 steps instead of 11 and 33 % instead of 0.6 % yield) for biomimetic ligands based on PQQ. We show that when studying biomimetics for MDH, larger metal ions and those with lower charge in this case promote the dehydrogenation reaction more effectively and that this is likely an effect of the ligand design which must be considered when studying biomimetics. To gain more information on the structures and impact of counterions of the complexes, we performed collision induced dissociation (CID) experiments and observe that the nitrates are more tightly bound than the triflates. To resolve the structure of the complexes in the gas phase we combined DFT-calculations and ion mobility measurements (IMS). Furthermore, we characterized the obtained complexes and reaction mixtures using Electron Paramagnetic Resonance (EPR) spectroscopy and show the presence of a small amount of quinone-based radical
Regulation of D-galacturonate metabolism in Caulobacter crescentus by HumR, a LacI-family transcriptional repressor
The oligotrophic freshwater bacterium Caulobacter crescentus encodes a cluster of genes (CC_1487 to CC_1495) shown here to be necessary for metabolism of D-galacturonate, the primary constituent of pectin, a major plant polymer. Sequence analysis suggests that these genes encode a version of the bacterial hexuronate isomerase pathway. A conserved 14 bp sequence motif is associated with promoter regions of three operons within this cluster, and is conserved in homologous gene clusters in related alpha-Proteobacteria. Embedded in the hexuronate gene cluster is a gene (CC_1489) encoding a member of the LacI family of bacterial transcription factors. This gene product, designated here as HumR (hexuronate metabolism regulator), represses expression of the uxaA and uxaC operon promoters by binding to the conserved operator sequence. Repression is relieved in the presence of galacturonate or, to a lesser extent, by glucuronate. Other genes potentially involved in pectin degradation and hexuronate transport are also under the control of HumR. Adoption of a LacI-type repressor to control hexuronate metabolism parallels the regulation of xylose, glucose, and maltose utilization in C. crescentus, but is distinct from the use of GntR-type repressors to control pectin and hexuronate utilization in gamma-Proteobacteria such as Escherichia coli
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