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61.
Wei Li Zhang Wei Pan Bin Luo Xi Hua Zou Meng Yao Wang 《Photonics Technology Letters, IEEE》2008,20(9):712-714
A theoretical construction of one-to-many (OTM) and many-to-one (MTO) chaos synchronization communications using semiconductor lasers is presented. One center laser provides strong injections (strong link) to other side lasers, and the side lasers also provide weak injections (weak link) to the center one. Simulation results show that the side lasers synchronize with the center laser through injection-locking. In addition, messages transmitted via the strong links or the weak links experience strong chaos pass filtering, enabling us to realize OTM and MTO communications. 相似文献
62.
The fracture toughness of brittle thermoset resins could be improved significantly by perfectly bonded tough, short fibers through both crack trapping and bridging effects. In this paper, the crack trapping effect was studied through the analysis of the change of strain energy associated with the crack propagation across a regular array of fibers, and the bridging effect was discussed based on the Andersson–Bergkvist model. The fracture resistance increases with the fiber volume fraction, and is independent of the elastic properties of the matrix, the crack length, and the cross-sectional diameter of the fibers. 相似文献
63.
In this paper, the vertical vibration of a flexible plate with rigid core resting on a semi-infinite saturated soil is studied analytically. The behavior of the soil is assumed to follow Biot’s poroelastodynamic theory with compressible soil skeleton and pore water, and the response of the time-harmonic excited plate is governed by the classical thin-plate theory. By virtue of the Hankel transform technique, the fundamental solutions of the skeleton displacements, stresses, and pore pressure are derived, and a set of dual integral equations associated with the relaxed boundary and completely drained condition at the soil-foundation contact interface are also developed. These governing integral equations are further reduced to the standard Fredholm integral equations of the second kind and solved by numerical procedures. Comparison with existing solutions for a rigid permeable plate on saturated soil confirms the accuracy of the present solution. Selected numerical results are presented to show the influence of the permeability, the size of the rigid core, and the plate flexibility on the dynamic interaction between the elastic plate with rigid core and the underlying saturated soil. 相似文献
64.
煤气吹扫时惰性气体抑爆用量的优选 总被引:1,自引:0,他引:1
运用惰性气体消防抑爆理论,采用数学积分法计算出吹扫煤气设施时抑爆所需最少惰性气体需要量. 相似文献
65.
聚苯醚磺酸锂/共聚醚复合物的离子导电性研究 总被引:1,自引:0,他引:1
合成了3种不同磺化度的聚苯醚磺酸锂(SPPOLi)与P(MEO16-AM)/SPPOLi复合物。研究了复合物的离子导电性与磺化度,组成比及增塑剂含量的关系。含40%(mass)增塑剂的复合物具有单离子导电特征,锂离子迁移数高达0.97,室温电导率达2×10-5S/cm。 相似文献
66.
川东地区井下套管损坏的原因分析及对策 总被引:4,自引:0,他引:4
本文就近年来在钻井施工中遇到的4口井发套管损坏的问题进行了原因分析,提出了防止井下套管损坏对策。 相似文献
67.
Unrecognized and untreated depression occurs frequently in Alzheimer's disease (AD) patients, adding to the agony already experienced by patient and caregiver. The authors screened AD patients living with a family caregiver for depression. Twelve patients with confirmed depression were treated in an open-label study with antidepressant medication, with dosage adjustment by a psychiatrist at Weeks 2, 4, 8, and 16. Data collection occurred at baseline, Week 4, and Week 16. Depression decreased significantly (p < .01). Contrary to expectations, patient functional capacity declined (p = .045). Cognition remained unchanged (p > .05). Caregiver burden, caregiver depressive symptomatology, and quality of life of patient and caregiver remained unchanged (p > .05). The authors conclude that depression in AD can be detected if a collateral source, such as the caregiver, is available. The depression can and should be treated. More research is needed to determine the impact on patient functioning, caregiver burden, caregiver depressive symptomatology, and quality of life of patient and caregiver. 相似文献
68.
69.
An aromatic diamine, CMOMDA, was synthesized and used as a chain extender for reaction injection molding (RIM) polyurethane–urea. The morphology and properties of CMOMDA-, DETDA-, and MDA-extended poly(ether–urethane–urea)s (PEUUs) were measured by IR, DSC, DMS, SEM, and tensile testing apparatus. Well-matched values of Ch and Xut,b/Ch were necessary for aromatic diamine-extended PEUU. DSC and SEM showed that the aggregation state of hard segments might undergo some changes with increasing hard-segment content. © 1994 John Wiley & Sons, Inc. 相似文献
70.
M Pan J Suárez de Lezo A Medina M Romero E Hernández J Segura F Melian F Wangüemert M Landin F Benítez M Amat F Velasco A Torres 《Canadian Metallurgical Quarterly》1997,80(10):1336-1338
Two hundred twenty-eight patients with successful coronary stent implantation were randomized either to protamine administration and femoral sheath removal (group I, n = 117) or no heparin neutralization and delayed sheath removal (group II, n = 111). The hospital stay after treatment was shorter in patients receiving protamine; therefore, protamine use for neutralizing circulating heparin may be safely administered immediately after stent implantation. 相似文献