Exploitation of SAR data for measurement of ocean currents and wave velocities

Methods of extracting information on ocean currents and wave orbital velocities from SAR data by an analysis of the Doppler frequency content of the data are discussed. The theory and data analysis methods are discussed, and results are presented for both aircraft and satellite (SEASAT) data sets. A method of measuring the phase velocity of a gravity wave field is also described. This method uses the shift in position of the wave crests on two images generated from the same data set using two separate Doppler bands. Results of the current measurements are pesented for 11 aircraft data sets and 4 SEASAT data sets

Evaluation of ERIM optically processed SEASAT SAR data

The results of three studies on the radiometric and geometric properties of optically processed SEASAT SAR imagery are summarized. The accuracy with which the image scale can be predicted based upon a knowledge of the SAR platform and recording system parameters and the processor characteristics was evaluated. The considerations involved in making radiometric measurements from image films, the use of point targets for calibrating the effects of Doppler spectrum shifts on the radiometric calibration of the SAR image data over extended swath lengths was evaluate

Tumor necrosis factor alpha and epidermal growth factor act additively to inhibit matrix gene expression by chondrocyte

The failure of chondrocytes to replace the lost extracellular matrix contributes to the progression of degenerative disorders of cartilage. Inflammatory mediators present in the joint regulate the breakdown of the established matrix and the synthesis of new extracellular matrix molecules. In the present study, we investigated the effects of tumor necrosis factor alpha (TNF-α) and epidermal growth factor (EGF) on chondrocyte morphology and matrix gene expression. Chondrocytes were isolated from distal femoral condyles of neonatal rats. Cells in primary culture displayed a cobblestone appearance. EGF, but not TNF-α, increased the number of cells exhibiting an elongated morphology. TNF-α potentiated the effect of EGF on chondrocyte morphology. Individually, TNF-α and EGF diminished levels of aggrecan and type II collagen mRNA. In combination, the effects of TNF-α and EGF were additive, indicating the involvement of discrete signaling pathways. Cell viability was not compromised by TNF-α or by EGF, alone or in combination. EGF alone did not activate NF-κB or alter NF-κB activation by TNF-α. Pharmacologic studies indicated that the effects of TNF-α and EGF alone or in combination were independent of protein kinase C signaling, but were dependent on MEK1/2 activity. Finally, we analyzed the involvement of Sox-9 using a reporter construct of the 48 base pair minimal enhancer of type II collagen. TNF-α attenuated enhancer activity as expected; in contrast, EGF did not alter either the effect of TNF-α or basal activity. TNF-α and EGF, acting through distinct signaling pathways, thus have additive adverse effects on chondrocyte function. These findings provide critical insights into the control of chondrocytes through the integration of multiple extracellular signals

Using actor networks in decision making during content-packaging development

In order to integrate sustainability in the development of content-packaging combinations, the consequences of decisions for the entire life cycle need to be analyzed in early stages of the development process. To adequately underpin these decisions, several aspects, for example the economic and the environmental impact, need to be assessed. A so-called actor network is developed to support designers in decision making. This publication examines practical use situations of this actor network tool based on information from research partners. Scenarios are written in order to depict requirements for the actor network tool, considering different users and functionalitie

Automated image segmentation and registration of vessel wall MRI for quantitative assessment of carotid artery vessel wall dimensions and plaque composition

The main goal of this thesis was to develop methods for automated segmentation, registration and classification of the carotid artery vessel wall and plaque components using multi-sequence MR vessel wall images to assess atherosclerosis. First, a general introduction into atherosclerosis and different stages of the disease were described including the importance to differentiate between stable and vulnerable plaques. Several non-invasive imaging techniques were discussed and the advantages of multi-sequence MRI were highlighted. Different novel automated image segmentation and registration techniques for analysis of the MRI images have been developed. A 3D vessel model to automatically segment the vessel wall was presented. Automated image registration was applied to correct for patient movement during the acquisition of an MRI scan and between MRI scans. The last topic is the automatic classification of the different plaque components which can be present inside the vessel wall. All techniques were developed and validated using relevant patient data and reference standards. The work presented is an important contribution to the automated analysis of multi-sequence MR vessel wall imaging of the carotid artery. These techniques can speed up the current manual analysis and are potentially more accurate and more reproducible.ASCI research school. Bontius Stichting inz. Doelfonds beeldverwerking. Library of the University of Leiden. Medis medical imaging systems bv, Leiden. Pie Medical Imaging BV, MaastrichtUBL - phd migration 201

Project-led education in packaging development and management

As an implicit subset of industrial design engineering, packaging development and management thereof has long been a changeling, because product and packaging development are usually regarded in a similar manner. At the same time, there is a clear difference between packaging design and product design. The packaging explicitly serves the content and, therefore, in most cases, packaging is of low economic value. For this reason, new packaging design is all too often subject to standard or existing packaging solutions. Besides this, packaging development has specific requirements, because it has to preserve and protect its content, which gives many technical requirements. Other important requirements are based on legislation, market acceptance, the environmental impact and usability.\ud \ud This implies that education in packaging development cannot be a carbon copy of the education in product development. Often, even more fields of expertise are involved, while having to meet all restrictions related to developing feasible and realistic packages in a shorter time-frame.\ud \ud This publication describes how project-led education is employed in an educational approach that allows students to adequately address the development of content-packaging combinations in a structured, effective and efficient manner. With this, the development efforts spent on product and packaging can become more in balance, not only doing justice to the separate life cycles of the two, but especially to the benefit of the combined life cycle of the content-packaging combination

Exploring Strategies To Promote Engagement And Active Learning Through Digital Course Design In Engineering Mathematics

This research explores the strategies and techniques used to foster and promote the engagement and active learning of engineering students within a digital course. This digital course has been developed to address the varying levels of understanding of fundamental mathematics among first-year engineering students, who often have disparate levels of prior knowledge at their high school completion. We observe an increasing need to bridge the widening gap between high school and university mathematics in order to prevent engineering students from being hindered in their academic successes due to a lack of prior mathematical understanding. With a team of engineers and mathematicians, both researchers and educators, we are developing a mathematics Bridging Course including the use of digital tools, such as videos, online interactions and technology-based assessments. These sources were created, investigated and/or modified to develop an engaging learning environment in which students are made aware of and guided through misconceptions and mistakes in their understanding of fundamental mathematics. In the development of this Bridging Course, we consider the importance of interactive learning and timely feedback for student learning. We investigate the impact of digital course design on students’ performance and learning outcomes using a qualitative approach. Students feedback within the first stage of the implementation of the course offered a positive assessment of the course, accentuating its inherent advantages and attributes. The students’ feedback proved to be an invaluable source of insights, specifically concerning the enhancement of question distractors, thus prompting revisions and augmentations in the assessment items employed

Modeling the effects of climate and land use change on carbon and trace gas budgets over the Amazon Region using NASA satellite products.

Abstract ID: 14. Publicado também on-line

Synthesis, Structure, and Properties of Compounds in the NaHSO_4−CsHSO_4 System. 1. Crystal Structures of Cs_2Na(HSO_4)_3 and CsNa_2(HSO_4_)3

Exploratory synthesis in the NaHSO₄-CsHSO₄ system, aimed at discovering novel proton conducting solids, resulted in the new compounds CsNa₂(HSO₄)₃ and Cs₂Na(HSO₄)₃. Single-crystal X-ray diffraction (performed at room temperature) revealed CsNa₂(HSO₄)₃ to crystallize in the cubic space group P2₁3 with lattice parameters a=10.568(2)Å and Z=4, whereas CS2Na(HSO₄)₃, studied by both single-crystal neutron and X-ray methods, crystallizes in the hexagonal space group P6₃/m. The latter compound has lattice parameters a=8.5712(17) and c=9.980(2)Å, and Z=2. The unit cell volumes are 1180.4(4) and 634.9(2)ų, respectively, giving calculated densities of 2.645 and 3.304 mg m⁻³. Refinement using all observed reflections yielded a weighted residual, R-w(F²), of 0.0515 based on F² X-ray values for CsNa₂(HSO₄)₃. For Cs₂Na(HSO₄)₃ the analogous X-ray and neutron values were 0.0483 and 0.1715, respectively. Both structures contain a single, crystallographically distinct, asymmetric hydrogen bond (as confirmed by NMR investigations) and unique, three-membered (HSO₄)₃ rings. The geometric match between the NaO₆ octahedra and the rings suggests the sodium polyhedra may serve to template the (HSO₄)₃ unit. In CsNa₂(HSO₄)₃ the rings form a distorted cubic close-packed array. The Cs atoms are located within the "octahedral" sites of this array, and the Na atoms, within the "tetrahedral" sites. The rings in CS₂Na(HSO₄)₃ are linked together by NaO6 octahedra to form infinite Na(HSO₄)₃ chains that extend along 001. The hexagonal compound exhibits disorder about the sulfate tetrahedron that suggests a P6₃/m → P6 phase transition may occur upon cooling