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Objective: To report the first case of ciliated hepatic foregut cyst in China, and review of literature to introduce the characteristics of this disease for doctors to recognize this disease. Method: Report the clinical procedure of diagnosis and treatment for the first case of ciliated hepatic foregut cyst in China, and to review the embryologic genesis, incidence, clinical manifestation, radiologic features and therapeutic principle of this disease. Results: We performed the resection for ciliated hepatic foregut cyst under laparoscopy; the patient recovered well after the procedure. Conclusion: Ciliated hepatic foregut cyst is quite rare clinically, belongs to non-parasitic, solitary and unilocular cystic lesion, is always less than 4 cm in diameter, mostly seen in the left lobe, and has the tendency of malignant change. It should be removed as soon as diagnosed. 相似文献
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The virtual laminated element method (VLEM) can resolve structural shape optimization problems with a new method. According
to the characteristics of VLEM, only some characterized layer thickness values need be defined as design variables instead
of boundary node coordinates or some other parameters determining the system boundary. One of the important features of this
method is that it is not necessary to regenerate the FE (finite element) grid during the optimization process so as to avoid
optimization failures resulting from some distortion grid elements. The thickness distribution in thin plate optimization
problems in other studies before is of stepped shape. However, in this paper, a continuous thickness distribution can be obtained
after optimization using VLEM, and is more reasonable. Furthermore, an approximate reanalysis method named “behavior model
technique” can be used to reduce the amount of structural reanalysis. Some typical examples are offered to prove the effectiveness
and practicality of the proposed method.
Project (No. 50075083) supported by National Natural Science Foundation of China 相似文献
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Two kinds of water-soluble and ultraviolet (UV) curable oligomers were synthesized and characterized. The oligomers were evaluated as resins for water-based UV curable coating. The rheology of the two oligomers' aqueous solutions was investigated in terms of solid fraction, pH dependence, and temperature dependence. The solutions were found to be Newtonian fluid showing rather low viscosity even at high solid fraction of 0.55. The drying process of the coatings and the properties of the cured coatings were studied by comparing them with water-dispersed UV-curable polyurethane methyl acrylate. It was evident that the water-soluble coating dried more slowly; and that the overall properties were inferior to those of the water-dispersed coating. 相似文献
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Ignoring the role of chance in science distorts the nature of the scientific process. Teachers can address this issue by means of several in-depth historical case studies, such as the discovery of electromagnetism by Oersted. Oersted was led to his lecture experiment by logic (two new hypotheses), but its success from the first trial was largely due to chance. Reproducing Oersteds experiment in the classroom complements the story by allowing students to see for themselves the role of some accidental factors, such as the choice of materials and instruments. The message to students is that chance and logic go together in science. 相似文献
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Quantum theory’s unusual predictions stem from its basic formalism which involves concepts like the wavefunction or probabilityamplitudes instead of probabilities. Many serious doubts have been raised about quantum theory’s connection with perceived classical dynamics. How does quantum mechanics, with all its strange ideas, unfold to give us the ‘reality’ of the familiar physical world? What is the connection between theclassical and thequantum! If quantum mechanics is, indeed, the fundamental theory of nature, as is widely accepted, then how does it explainclassicality! In the following, some of the fascinating conceptual problems of quantum mechanics are highlighted. The ‘environment-induceddecoherence’ approach is then discussed as one practical attempt at explaining the emergence of a classical world from an underlying quantum substrate 相似文献
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Suction foundations have been deployed in the last three decades in a growing number of offshore developments, for bottom-fixed and floating structures, in shallow and deep waters, many of them successfully. Suction foundations, traditionally used as anchors and jacket foundations in the oil and gas industry, are now also used in the offshore renewable (wind) industry, e.g. for monopods, tripods, and jackets. When technically feasible, suction foundations are often cheaper than pile foundations. Additionally, their installation is relatively noise-free and, by applying overpressure, they can be removed during decommissioning. This paper focuses on the more complex design issues and some pitfalls related to suction foundation design. Additionally design practices and recommendations for suction caisson design, including installation and extraction feasibility, foundation resistance, settlements and response in sand, clay and layered soil profiles, will be presented for basic understanding. 相似文献
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Although history of science is a potential resource for instructional materials, teachers do not have a tendency to use historical
materials in their lessons. Studies showed that instructional materials should be adaptable and consistent with curriculum.
This study purports to examine the alignment between history of science and the curriculum in the light of the facilitator
model on the use of history of science in science teaching, and to expose possible difficulties in preparing historical materials.
For this purpose, qualitative content analysis method was employed. Codes and themes were defined beforehand, with respect
to levels and their sublevels of the model. The analysis revealed several problems with the alignment of historical sources
for the physics curriculum: limited information about scientists’ personal lives, the difficulty of linking with content knowledge,
the lack of emphasis on scientific process in the physics curriculum, differences between chronology and sequence of topics,
the lack of information about scientists’ reasoning. Based on the findings of the analysis, it would be difficult to use original
historical sources; educators were needed to simplify historical knowledge within a pedagogical perspective. There is a need
for historical sources, like Harvard Case Histories in Experimental Science, since appropriate historical information to the
curriculum objectives can only be obtained by simplifying complex information at the origin. The curriculum should leave opportunities
for educators interested in history of science, even historical sources provides legitimate amount of information for every
concepts in the curriculum. 相似文献
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