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981.
Yoshimura T. Kumai K. Mikawa T. Ibaragi O. Bonkohara M. 《Electronics Packaging Manufacturing, IEEE Transactions on》2002,25(1):19-25
"Photolithographic packaging (PL-pack) with selectively occupied repeated transfer (SORT)" is proposed for optoelectronic microsystem integration. PL-pack with SORT integrates different types of thin-film device pieces into one substrate with desired configurations using an all-photolithographic process. A process design example is presented for a scalable film optical link multichip-module (S-FOLM). A preliminary estimation reveals that PL-Pack with SORT will achieve III-V epitaxial material saving of <1/100 and module cost reduction of <1/10, compared with flip-chip-bonding-based packaging. The result indicates that the process will save on cost and resources simultaneously. A critical issue is how to simplify the procedure for distributing thin-film device pieces onto a substrate. SORT is found to reduce the distribution step count typically by factor of <1/10-1/10000 compared with the conventional one-by-one method. PL-pack with SORT will be extended to the 3R process (reduce, reuse, recycle), which is generally applied to a variety of device/module fabrications 相似文献
982.
Effective removal of unwanted particles from a molten metal alloy by flotation relies on purging a gas into the melt through
a rotating impeller. This device is commonly known as a rotary degasser. Unwanted particles in the melt attach to the rising
gas bubbles and rise to the slag layer where they are removed from the metal bulk. In addition, the turbulence created by
the rotating impeller causes the randomly distributed solid particles to agglomerate into relatively large clusters. These
clusters float up or settle down due to the difference between their density and that of the melt. A mathematical model has
been developed to describe the particle dynamics and particle agglomeration that occur during the rotary degassing of aluminum
melts. While previous investigations addressed particle collisions in low intensity turbulent fields where the size of the
colliding particles is smaller than the Kolmogorov length scale, this model is more encompassing as it considers both low
intensity and high intensity turbulence. Consequently, this model is more representative of a typical industrial rotary degassing
operation. 相似文献
983.
984.
985.
A mathematical model of evaporation process from a laminar falling liquid film on a vertical plate of constant temperature is presented. The model is developed with and without interfacial shear stress due to the vapor flow at the liquid film surface. The vapor pressure drop, vapor exit velocity and cooling rate are calculated for different liquid mass flow values. It is shown that lower liquid mass flow produces higher cooling rate. The results also show that the interfacial shear stress has a considerable negative effect on the cooling rate. It is proved that there exists an optimum distance between the plates, which gives the maximum volumetric cooling rate. 相似文献
986.
987.
988.
989.
Batch process industries are characterized by complex precedence relationships between operations, which renders the estimation
of an acceptable workload very difficult. A detailed schedule based model can be used for this purpose, but for large problems
this may require a prohibitive large amount of computation time. We propose a regression based model to estimate the makespan
of a set of jobs. We extend earlier work based on deterministic processing times by considering Erlang-distributed processing
times in our model. This regression-based model is used to support customer order acceptance. Three order acceptance policies
are compared by means of simulation experiments: a scheduling policy, a workload policy and a regression policy. The results
indicate that the performance of the regression policy can compete with the performance of the scheduling policy in situations
with high variety in the job mix and high uncertainty in the processing times.
Correspondence to: C.V. Ivanescu 相似文献
990.
V. B. Baiburin Yu. P. Volkov E. M. Il’in S. V. Semenov 《Technical Physics Letters》2002,28(12):981-982
The surface of a palladium-barium cathode was studied using scanning probe microscopy techniques. Data from the tunneling spectroscopy showed the pattern of the electron work function distribution over a microscopic region on the emitter surface. This pattern is compared to the distribution of various phases in the palladium-barium alloy employed. 相似文献