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991.
Editorial     
  相似文献   
992.
993.
As packaging technology advances to wafer level chip scale packaging (WLCSP) to enable reduced chip size and manufacturing cost, circuit edit has become a critical issue for the fully packaged integrated circuits (ICs). These advanced package types cannot be rebuilt on a single chip; therefore, function testing after circuit edit of WLCSP faces challenges. Furthermore, there are routings at the redistribution layer of WLCSP ICs. Circuit edit was applied on both the chip and the package level. In this paper the focused ion beam was applied to mill the organic material of the package structure to expose underlying ICs, instead of chemically destroying the packaging. Metal line cutting and conductive path deposition were also developed by a beam-based technique. These new approaches make the direct edit of electrical circuitry possible not only in ICs but also at package level. Therefore, for the debug process and for failure analysis, the WLCSP ICs have negligible damage and negligible signal integrity loss by retaining the original packaging structure.  相似文献   
994.
Bulk (Mg1.02B2)1−x Sn x samples (x = 0.0, 0.01, 0.03 and 0.05) were synthesized by in situ sintering at 850 °C for one hour. Based on the phase identification and microstructure observation, the Mg2Sn and Sn impurities are found as the main impurities in Sn-doped samples. According to the magnetization measurements, the low doping level of Sn was observed to have small influence on the grain connectivity, and thus a high critical current density was maintained at low field. However, the values of the critical current density at high field in the Sn-doped samples show a little decrease.  相似文献   
995.
Interfacial assembly of sandwich mixed (phthalocyaninato)(porphyrinato) rare earth triple-decker complexes [(Pc)Eu(Pc)Eu(TPyP)] (1) and [(TPyP)Sm(Pc)Sm(TPyP)] (2) (Pc = phthalocyaninate, TPyP = meso-tetrakis(4-pyridyl)porphyrinate) has been comparatively studied at the air/pure water and the air/CdCl2 aqueous solution subphase interfaces. Surface pressure-area isotherms revealed the remarkable increase of limiting mean molecular area of the triple-deckers with the presence of Cd2+, suggesting the occurrence of in situ interfacial coordination. The formation of coordination bonds between the pyridyl groups of TPyP macrocycles in the triple-deckers and Cd2+ ions from the subphase was further supported by FT-IR spectroscopic data. Electronic absorption measurements showed the formation of J-aggregates of the triple-decker molecules in the interfacial assembled films.  相似文献   
996.
Certain equivalent conditions are given for the equivalence of linear codes using the properties of the relative subcodes derived from the relative generalized Hamming weight.  相似文献   
997.
998.
A stochastic constitutive theory is proposed in this work to propagate microstructure uncertainties in computational multiscale continuum models to bulk multiresolution material behavior. Ubiquitous fine resolution uncertainty sources influencing prediction of material properties based on their structures are categorized in detail, and this research transmits these uncertainties to coarser material resolutions by introducing a stochastic constitutive theory deduced from volume element simulations. To implement the stochastic upscaling process, two advanced uncertainty quantification methods are examined: statistical copula functions and random process polynomial chaos expansion. Both methods confront the mathematical difficulty in randomizing constitutive laws by capturing the marked correlation among constitutive parameters seen in complex materials, thus the results proffer a more accurate probabilistic estimation of constitutive material behavior. The contribution of this work is twofold: uncertainty is propagated from heterogeneous material “structure” to material “property” via the stochastic constitutive theory, and rigorous, data-driven mathematics are formalized to represent complicated dependence structures in multivariate statistical distributions. To the authors’ knowledge, this is the first work in multiresolution mechanics that presents an approach to computationally derive correlation functions from numerical experiments, as opposed, for instance, to assuming one a priori. The method put forth in this research, though quite general, is applied to a mathematical example and plastic, high strength steel alloy for demonstration. Results include stochastic constitutive curve confidence intervals for the material stress–strain response and qualitative comparisons of the two stochastic methods detailed herein.  相似文献   
999.
介绍了厚度方向性能Q345EZ35中厚板开发的主要技术和关键环节,该中厚板的实物质量符合国家标准要求。  相似文献   
1000.
Al-12Si-11.8Mg-6.5Ti alloy samples were solidified in high magnetic fields with various magnetic field gradients. The effects of high magnetic fields on the distribution and alignment of primary phases in the alloys were investigated. It was found that the uniform magnetic field could improve the homogeneity of the primary Mg2Si, whereas the magnetic field gradient caused the two-layer core grains ((Al,Si)3Ti and Ti5Si4) to segregate at certain regions of the samples depending on the magnetic field gradient direction. The primary (Al,Si)3Ti strips were oriented with their c axes perpendicular to the magnetic field direction and aligned with their long axes along the magnetic field direction. The changes in the distribution of the primary Mg2Si and two-layer core grains were caused by the Lorentz force and magnetic force, which could counteract and cause the migration of these phases, respectively. The alignment of the primary (Al,Si)3Ti could be attributed to the combination of the magnetic orientation and solute redistribution.  相似文献   
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