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121.
122.
Itagaki M. Amami K. Tomura Y. Yuhaku S. Ishimaru Y. Bessho Y. Eda K. Ishida T. 《Advanced Packaging, IEEE Transactions on》1999,22(3):366-371
A new chip scale package (CSP) using an organic laminated substrate called μCSP was developed, which was fabricated using ALIVH substrate as a interposer and stud-bump-bonding (SBB) flip-chip technology. The ALIVH substrate is a multilayered organic substrate with inner via holes in any layer. The newly developed CSP-L using ALIVH substrate realized a miniaturization of its package size to the same as a CSP using a ceramic substrate (CSP-C). In order to perform the SBB flip-chip bonding onto the ALIVH substrate, an excellent coplanarity of the substrate surface was required. The required coplanarity was obtained using a fixture during the SBB flip-chip bonding process. The first-level packaging reliability and the second-level packaging reliability onto ALIVH mother board were evaluated. The resulting reliabilities were good enough to apply to practical use 相似文献
123.
X. J. Liu I. Ohnuma R. Kainuma K. Ishida 《Journal of Phase Equilibria and Diffusion》1999,20(1):45-56
A thermodynamic calculation of the Al-Mn binary system that takes into account recent experimental results and includes five
intermetallic compounds and all the solid-solution phases is presented. The Gibbs energy of the body-centered cubic (bcc)
phase has been described on the basis of the two-sublattice model that includes the second-order A2/B2 ordering reaction as well. A consistent set of optimized thermodynamic parameters has been arrived at for describing the
Gibbs energy of each phase in this system leading to a better fit between calculation and experiments. 相似文献
124.
This paper proposes aDistributed Vision System (DVS), which is an intelligent infrastructure for mobile robots consisting of manyvision agents (VAs) embedded in an environment. The system monitors the environment from various viewing points with the VAs, maintains the dynamic environment models, and provides various information to robots. Based on this concept, we have developed a prototype of the DVS which consists of sixteen vision agents and simultaneously navigates two robots in a model town. 相似文献
125.
L. ZhouC.P. Wang Y. YuX.J. Liu H. ChinenT. Omori I. OhnumaR. Kainuma K. Ishida 《Journal of Alloys and Compounds》2011,509(5):1554-1562
The isothermal sections of the Co-Nb-Ta ternary system at 900 °C, 1000 °C, 1100 °C, 1200 °C, 1300 °C have been experimentally determined by electron probe microanalysis (EPMA) and X-ray diffraction (XRD) techniques on the equilibrated alloys. On the basis of the experimental data investigated in the present work, the phase equilibria in the Co-Nb-Ta system has been thermodynamically assessed by using CALPHAD (CALculation of PHAse Diagrams) method, and a consistent set of the thermodynamic parameters leading to reasonable agreement between the calculated results and experimental data was obtained. 相似文献
126.
Hajime Araki Taichi Kaji Masahito Yamamoto Keiji Suzuki Azuma Ohuchi 《Electrical Engineering in Japan》2001,135(4):43-51
The optimal sequential problem is defined as the problem of finding the minimum cost partition of the nodes of a directed acyclic graph into subsets of a given size, subject to the constraint that the precedence relationships among the elements are satisfied. A heuristic algorithm based on tabu search has been proposed for this problem [2]. However, there is a tendency for the solutions obtained by tabu search to become trapped in bad local optima in parallel graphs with random edge costs. In this paper we present a genetic algorithm for the optimal sequential partitioning problem. We develop an effective two‐point partial order crossover satisfying sequential conditions, which preserve better blocks that have a larger sum of edge costs. In this crossover we introduce the roulette selection method to escape local optima. We also assess the effectiveness of the algorithm. The results show that this proposed algorithm outperforms any other algorithm using tabu search in terms of solution quality. © 2001 Scripta Technica, Electr Eng Jpn, 135(4): 43–51, 2001 相似文献
127.
128.
Optical, electrical, and structural properties of Al2O3 films subjected to silicon-ion implantation and annealing were investigated by means of photoluminescence measurements, current-voltage
measurements and transmission electron microscopy. Transmission electron microscopy revealed that silicon nanocrystals were
epitaxially formed in ϑ-Al2O3. Visible photolum inescence was observed, for the first time, from Al2O3 films containing silicon nanocrystals. Observed visible photoluminescence seems to be related to quantum size effects in
silicon nanocrystals as well as localized radiative recombination centers located at the interface between silicon nanocrystals
and matrix, similar to porous Si and other Si nanostructures. The conduction mechanism in the samples was studied by using
dc current-voltage measurements. The conduction properties depend on temperature and applied electric fields. The conduction
behavior in low electric fields consists of thermally activated region dominated by the Schottky conduction and nonthermally
activated region in which carrier transport is controlled by space-charge-limited currents. The conduction behavior under
relatively high electric fields is almost independent of temperature and well fitted by space-charge-limited conduction. 相似文献
129.
An investigation is reported in which, to ensure that the noise control of a shuttle-weaving mill set the restricted noise level at the boundary between the sill and its neighbours, the noise-transmission loss of twelve kinds of mill wall was investigated by using the “reverberant room versus reverberant room” method. On the basis of the results obtained, several plans for the reconstruction of a shuttle-weaving mill are suggested, and the results obtained after such a reconstruction are discussed. 相似文献
130.
The electromagnetic induction method utilising eddy current plays an important role in a non-destructive material test. In testing slab-type material by electromotive force method, there is the fork-shaped coil method, which has two coils placed on both sides of the test piece. In most studies, circular coils have been analysed. However, it has been pointed out quantitatively that a rectangular coil is more useful than a circular coil for a non-destructive test. The authors derive a rigid theoretical formula with a test theory experiment. 相似文献