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51.
Dongwook Lee Kiseon Kim 《Electronics letters》1998,34(15):1474-1476
The authors suggest a novel virtual circuit connection method based on the reverse traversing technique to minimise the waste of network bandwidth resources, when the Internet protocol multicast is interoperated using the resource reservation protocol over an asynchronous transfer mode network. Simulation results show that, as the number of receivers increases, the bandwidth requirements on all links of the network of the proposed scheme become more advantageous than those of other conventional methods 相似文献
52.
HJ Lee HK Ha MH Kim YK Jeong PN Kim MG Lee JS Kim DJ Suh SG Lee YI Min YH Auh 《Canadian Metallurgical Quarterly》1997,169(2):517-520
OBJECTIVE: The purpose of this study was to evaluate ERCP and CT findings of ectopic drainage of the common bile duct into the duodenal bulb. CONCLUSION: Although rare, the diagnosis of ectopic drainage of the common bile duct into the duodenal bulb is important to prevent inadvertent damage during biliary tract or gastric surgery and to clarify the cause of chronic peptic ulcers. 相似文献
53.
We present a technique for in situ lens nucleus emulsification using low phaco power and high vacuum, a continuous curvilinear capsulorhexis, and hydrodelineation. Emulsification is done with the phaco tip slanted down 30 or 45 degrees. Cutting and aspiration do not cause an undesirable energy loss. This technique can be combined with the nuclear chopping or divide and conquer methods because of its ability to drill and hold the nucleus. Posterior capsular rupture is prevented because the separated epinucleus acts as a barrier between the nucleus and the cortex. The low power used minimizes the energy transfer to the corneal endothelium. This technique is particularly useful in eyes with brunescent cataract. 相似文献
54.
Jae-Chul Lee Ho-In Lee Gyeung-Ho Kim Jung-Ill Lee 《Metallurgical and Materials Transactions A》1997,28(5):1251-1259
Interfacial reactions in the squeeze-cast SAE 329 Al alloy reinforced with SAFFIL and carbon fibers were investigated using
scanning and transmission electron microscopy and secondary ion mass spectroscopy. The SiO2 layer added as a binder for the preform of SAFFIL fiber appeared to prevent excessive reaction between the fiber and the
molten Al alloy during casting. In the as-cast composite, the reaction between the SiO2 layer and the Al alloy is considered to produce MgO crystals in the vicinity of SAFFIL fiber. With subsequent heat treatment
of the composite to the T6 condition, small crystals of MgO and MgAl2O4 were found to form at the surface of SAFFIL fiber as a result of interfacial reaction between the SiO2 layer and the Al alloy. Even at the T6 condition, significant reactions between the Al alloy and SAFFIL fiber itself were
not observed, indicating the effective role of the binder layer in suppressing the degradation of SAFFIL fiber by reaction
with the Al alloy. 相似文献
55.
Flexible manufacturing systems (FMSs) are able to process a wide variety of operations, but the specific mix of operations that can be performed at any point in time depends upon the combination of tools loaded onto the machines. The machines have tool magazines with finite capacities. We consider the problem of assigning operations and their associated tools to machines (or groups of machines) to maximize the throughput for a specified steady-state mix of orders. Since this objective is difficult to deal with directly, we use an intermediate objective of meeting workload targets for each machine group as closely as possible. A certain form of this intermediate objective has been shown to correlate highly with the original objective.
Since it is computationally intractable to find optimal solutions for problems with more than 20 operations, fast heuristic algorithms are developed. These algorithms are adapted from multi-dimensional bin-packing algorithms. Computational results are reported. 相似文献
Since it is computationally intractable to find optimal solutions for problems with more than 20 operations, fast heuristic algorithms are developed. These algorithms are adapted from multi-dimensional bin-packing algorithms. Computational results are reported. 相似文献
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The incidence of stress fractures is increasing among competitive and recreational athletes as well as among children and the elderly. By understanding the continuum of bone's response to stress and maintaining an appropriate index of suspicion, the health care provider can diagnose these injuries appropriately. An accurate history and examination is essential and will differentiate stress fractures from other stress reactions. The more common stress fractures are discussed. 相似文献
59.
OBJECTIVE: To evaluate the therapeutical mechanism of Bushen Shengxue Paste (BSSXP) on anemia. METHODS: Chronic renal failure induced anemia patients were treated with BSSXP, clinical manifestation, anemia and renal function as indicators were observed in patients. The erythropoietin (EPO) and inhibition of colony-forming unit-erythrocyte (CFU-E) in patients' serum were determined by CFU-E in vitro. RESULTS: The patients' symptoms, renal function and anemia were improved after administration with BSSXP 1-2 course. EPO in serum was slightly increased. The inhibition of CFU-E in patient's serum was significantly decreased. CONCLUSIONS: BSSXP could improve the anemia degree, its mechanism might be through clearing the inhibitor of CFU-E in serum. 相似文献
60.
For the first time, the surface metal on nonalloyed ohmic electrodes is found to significantly change the profiles of gate grooves, when resist openings are employed to monitor drain current during wet-chemical gate recess for sub-micron InAlAs/lnGaAs heterojunction field-effect transistors (HFETs). The surface metal of Ni enhances the etching rate in comparison with that in the absence of electrodes by a factor of 4 and 10, laterally and vertically, which is favorable to fabricate deep gate grooves with small side etching. The Pt surface metal, however, leads to preferential etching of InGaAs over InAlAs, which can be useful to realize large side etching. The existence of an electrochemistry-related etching component, which arises when the ohmic electrodes are present during recess etching, is considered to be responsible for these behaviors 相似文献