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21.
Characterization of microstructures with features from submicrometers to hundreds of micrometers requires versatile methods. Profilometry and optical microscopy cannot cope with submicrometer features, and atomic-force microscopy, scanning-electron microscopy, and near-field microscopy are inherently slow, off-line methods. In optical scatterometry, the laser light scattered from a sample is measured and the sample profile is subsequently characterized. We propose the use of a two-stage model based on neural networks: rough categorization followed by refinement, thus reducing the need for prior information on the sample. We simulate the method for a submicrometer diffraction grating characterized by five parameters. It is shown that intensity measurements of few diffraction orders by use only of one wavelength are enough to yield rms errors of less than 2 nm for the parameters (approximately 2-3% of the optimal values of the parameters). 相似文献
22.
Tuomo P Matti L Hannu P Pentti R Henna N Pertti T 《Journal of materials science. Materials in medicine》2004,15(3):275-281
Self-reinforced poly(L/DL)lactide 70:30/bioactive glass [SR-P(L/DL)LA/bioactive glass] composite rods, 2 mm in diameter and 36 mm in length, were implanted into the dorsal subcutaneous tissue of 16 rats. Osteotomies of the distal femur were fixed with these rods (2 x 15 mm) in 64 other rats. The follow-up times varied from one week to one year. After sacrifice, three-point bending and shear tests, and molecular weight measurements were performed for subcutaneously placed rods. Radiological, histological, histomorphometrical, microradiographic, and oxytetracycline-fluorescence studies of the osteotomized and intact control femora were performed. At 24 weeks the mechanical properties had decreased significantly. Thirty-nine osteotomies healed uneventfully. One of the 64 evaluated osteotomies showed signs of infection at six weeks, and there were 19 non-unions and six delayed unions. In 20 operations the fixation was loose and out of these 14 non-unions were observed. No gross signs of inflammatory or foreign-body reactions were observed. The present investigation showed that the mechanical strength and fixation properties of SR-P(L/DL)LA/bioactive glass composite rods are suitable for fixation of cancellous bone osteotomies in rats as long as the operative technique is correct. The present article is the first report on the application of SR-P(L/DL)LA/bioactive glass composite rods for fixation of cancellous bone osteotomies. 相似文献
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We consider the scattering of light by single wood fibers both theoretically and experimentally. We describe the size and the shape distributions and the internal structure and chemical composition of the wood fibers. We have modeled the random shape of the hollow, cylindrical wood fiber by using multivariate lognormal statistics. We have computed wood-fiber absorption and scattering cross sections, asymmetry parameters, and scattering phase matrices in the ray-optics approximation. Finally, we have provided experimental results from angular scattering measurements for wood fibers and present what we believe is the first comparison between these measurements and ray-optics computations for Gaussian random wood-fiber models. In spite of the complicated internal structure of the wood fiber, our model together with the ray-optics treatment explains the scattering measurements surprisingly well. 相似文献
25.
The aim of this research was to study the nature of creative tension of engineering students in South Korea. The creative tension was analyzed according to relevant competences in project managers' work role. Most of the subjects who participated in this study were part‐time students who worked as managers in manufacturing and industrial companies. The application used for collecting and analyzing data was the project managers' work‐role–based competence application, Cycloid. Data were collected on the Internet by self‐evaluation. The constructed competence model of the Cycloid application was added into the Evolute self‐evaluation system utilizing fuzzy logic. The application was able to identify students' current state and personal aims and the creative tension essential for their personal development. The Cycloid application can be utilized in developing the professional competencies of individuals, teams, and organizations. © 2007 Wiley Periodicals, Inc. Hum Factors Man 17: 511–520, 2007. 相似文献
26.
A double approach method for versatile detection of similar objects from the real environment is introduced. By searching both the shape and textural data from the video image, it is possible to solve a generalized location problem without a loss in overall reliability in near–real time. A forest forwarder is used as a proof-of-concept application for the technique. 相似文献
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Ohne Zusammenfassung 相似文献
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A passive chilled beam is a source of natural convection, creating a flow of cold air directly into the occupied zone. Experiments were conducted in a mock-up of an office room to study the air velocities in the occupied spaces. In addition, velocity profiles are registered when underneath heat loads exist and the cool and warm air flows interact. Experimental laboratory study revealed that in the case of the underneath heat gains, even no upward plume was generated and the dummy only acted as a flow obstacle, having a significant effect on the velocity profile. Furthermore, in an actual occupied office environment, the thermal plumes and the supply air diffuser mixed effectively the whole air volume. The maximum air velocity measured was still below 0.25 m/s with the extremely high heat gain of 164 W/m2. The results demonstrate that analysis methods were the interaction of convection flow and jet are not taken into account could not accurately describe air movement and draught risk in the occupied room space. 相似文献
30.
Hannu Linkola 《Landscape Research》2015,40(8):939-954
AbstractIn 2010, the Finnish Ministry of the Environment launched a re-evaluation and revision of the 1993 inventory of Nationally Valuable Landscape Areas (NVLAs). While the inventory works for implementation of the National Land Use Guidelines, it also showcases the use of landscapes in Finnish national heritage policy. Based on critical readings of three influential Finnish administrative landscape policy reports, I claim that NVLAs, as tools of heritage policy, are based on the approaches and methodologies that have supported Finland’s development into a modern nation state by providing tools for intellectual governance of the national past and territory. Rather than meeting the diversity of landscape conceptions, as defined in the European Landscape Convention, the NVLAs run a risk of being in conflict with citizens and actors that do not share the administrative assumption of landscapes as public containers of national heritage. 相似文献