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101.
Thongvigitmanee T. May G.S. 《Electronics Packaging Manufacturing, IEEE Transactions on》1999,22(4):314-318
Integrated decoupling capacitors for MCM-L/D technology are an important component for next-generation electronic packaging applications. This paper presents a statistically designed experiment for systematic characterization of the dielectric constant and loss tangent of integrated capacitors formed by mixing lead magnesium niobate (PMN) particles into polyimide and benzocyclobutene (BCB) polymer dielectric layers. We determine these quantities as a function of the type of polymer material, a volume fraction of ceramic in the polymer matrix, a polymer cure time, and polymer cure temperature. These factors have been examined by means of a D-optimal experiment. Results indicate manipulation of each of the four factors over the ranges examined lead to considerable variation in dielectric constant and loss tangent. Based on data from these experiments, we train neural networks to model this process variation as a function of above variables. Using this methodology, we determine proper combinations of polymer/ceramic materials and processing conditions to achieve desirable electrical properties 相似文献
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Mehrdad Rafat May Griffith Malik Hakim Lea Muzakare Frank Li K.C. Khulbe Takeshi Matsuura 《应用聚合物科学杂志》2007,106(3):2056-2064
Argon plasma treatment enhanced the attachment of epithelial cells to a collagen‐based artificial cornea crosslinked using glutaraldehyde (GA) and glutaraldehyde‐polyethylene oxide dialdehyde (GA‐PEODA) systems. The epithelialization of untreated and treated surfaces was evaluated by the seeding and growth of human corneal epithelial cells. Characterization of polymer surface properties such as surface hydrophilicity and roughness was also made by contact angle measurement and atomic force microscopy, respectively. Contact angle analysis revealed that the surface hydrophilicity significantly increased after the treatment. In addition, AFM characterization showed an increase in surface roughness through argon plasma treatment. Based on the biological and surface analysis, argon plasma treatment displays promising potential for biocompatibility enhancement of collagen‐based artificial corneas. It was also found that the cell attachment to artificial cornea surfaces was influenced by the combined effects of surface chemistry (i.e., surface energy), polymer surface morphology (i.e., surface roughness), and polar interactions between functional groups at the polymer surface and cell membrane proteins. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
104.
Do clinic-referred children and their parents agree on the problems for which treatment is undertaken? The authors asked 381 outpatient-clinic-referred children and their parents to list, independently, the child's target problems. Of the parent-child pairs, 63 % failed to agree on even a single problem. When problems were grouped into broad categories (e.g., delinquent, withdrawn), more than a third of the pairs still failed to agree on a single broad problem area. Parent-child agreement was higher for externalizing than for internalizing problem categories (though poor for both). Low parent-child agreement may help explain the poor outcomes often reported for clinic-based child therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
L Struillou C Rabaud N Bischoff MA Preiss T May P Canton 《Canadian Metallurgical Quarterly》1997,26(25):1192-1194
BACKGROUND: Cardiac localization of hydatiosis is uncommon, involving 0.5 to 2% of all cases. CASE REPORTS: The first patient was a 15 year old adolescent whose cardiac hydatidosis was revealed by tamponade. The second case was discovered in a 28-year-old woman without cardiac signs who was explored for allergy manifestations with fever, urticaria and joint point. Both patients underwent surgery. Eighteen months after the operation, the second patient developed hemiplegia leading to the discovery of multi-organ localizations (brain, spleen, kidney) which were not evidenced at the initial work-up. The neurological deficit and brain cysts regress with albendazole treatment. DISCUSSION: The risk of rupture of the cardiac hydatic cyst requires rapid surgical cure. Medical treatments are discussed. Anti-hydatic drugs can be used alone in case of a contraindication for surgery. In other patients they are given during the perioperatie period and for a prolonged period after surgery. 相似文献
106.
Hartmann and Hasher (1991) used a garden-path task in which younger and older adults generated the final word for each of a series of high-cloze sentences. Under instructions to remember the final word, the experiment included critical sentences for which the generated word was replaced by a new, to-be-remembered target. Using an implicit priming task, the first experiment replicated a basic finding: Younger adults showed priming only for the target words, whereas older adults showed priming for both the generated and target words. Two experiments explored the boundary conditions. One showed that an additional sentence that interpreted the new target word enabled older adults to narrow access to only the target word. The provision of additional time following the introduction of the new target word did not. Specific information, not more time, is required for inefficient inhibitory mechanisms to clear the recent past from memory. 相似文献
107.
JR Horwitz MD Custer BH May JR Mehall KP Lally 《Canadian Metallurgical Quarterly》1997,32(11):1601-1603
BACKGROUND/PURPOSE: Laparoscopic appendectomy is becoming the preferred technique for treating acute appendicitis. However, recent literature on adults suggests that laparoscopic appendectomy may increase the risk for postoperative infectious complications in complicated (gangrenous or perforated) cases. This study was undertaken to compare the results of open versus laparoscopic appendectomy for complicated appendicitis in children. METHODS: A retrospective review from two institutions was performed for all children treated operatively for complicated appendicitis from January 1994 through November 1996. RESULTS: Fifty-six cases were identified. Twenty-seven children underwent laparoscopic appendectomy, whereas 22 underwent open appendectomy. Seven children underwent conversion from laparoscopic to open surgery. Operating times and length of hospital stay did not differ significantly between the laparoscopic and open groups. Postoperative complications developed in 24 children (42.8%). Complications were more frequent after laparoscopic appendectomy compared with open appendectomy (56% v 18%, P = .002). A postoperative intraabdominal abscess (IAA) developed in 14 children (25%). An IAA occurred in two children after open appendectomy compared with 11 children after laparoscopic appendectomy (9% v 41%, P = .01). CONCLUSION: The findings suggest that laparoscopic appendectomy should be avoided in children who have complicated appendicitis because of the increased risk for postoperative intraabdominal abscesses. The authors propose a prospective, randomized trial to verify this finding. 相似文献
108.
A holographic matched filter is used to measure the changes in the output of a dual-mode fiber undergoing axial strain. The hologram is formed by interfering collimated light from a single-mode reference fiber and an unstrained dual-mode sensor fiber on a small piece of holographic material. When the hologram is illuminated by the strained sensor fiber, the cross-correlation field comparing the dual-mode output and its previous state, as recorded in the hologram, is collected, focused into a pick-up fiber, and sent to a photodiode. This arrangement allows for a compact, in-line method for full-field processing of the strain-induced changes in phase and amplitude in the sensor fiber. Other uses of such fiber-based correlators are suggested 相似文献
109.
110.
AbstractThis paper describes experiments on multiaxial fibre reinforced plastic laminates, which were performed to obtain calibration data for numerical fatigue analyses. For this purpose, fatigue tests of laminates with multidirectional layers subjected to constant amplitude and block loading (0?≤?R?<?1 or R>1) were analysed. The presented simulation results display the fatigue behaviour of carbon fibre reinforced plastics for unidirectional loading conditions and a selected laminate. 相似文献