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Microprocessors continue on the relentless path to provide more performance. Every new innovation in computing-distributed computing on the Internet, data mining, Java programming, and multimedia data streams-requires more cycles and computing power. Even traditional applications such as databases and numerically intensive codes present increasing problem sizes that drive demand for higher performance. Design innovations, compiler technology, manufacturing process improvements, and integrated circuit advances have been driving exponential performance increases in microprocessors. To continue this growth in the future, Hewlett Packard and Intel architects examined barriers in contemporary designs and found that instruction-level parallelism (ILP) can be exploited for further performance increases. This article examines the motivation, operation, and benefits of the major features of IA-64. Intel's IA-64 manual provides a complete specification of the IA-64 architecture 相似文献
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哈达 《数码设计:surface》2008,(3X):5-6
设计的功能是以人为本,丰富和升华人们的生理体验和心理体验以提升生活品质,传递信息和新的思维方式;设计作品的优劣从某种角度来说是设计思维深入程度决定的;设计思维是以个人对世界的认识为基础的;人对世界认识的程度实际上也就是设计思维深入的程度,因此我们应弄清自己思维的渊源,树立正确的世界观。 相似文献
75.
哈达 《数码设计:surface》2008,(3):5-6
设计的功能是以人为本,丰富和升华人们的生理体验和心理体验以提升生活品质,传递信息和新的思维方式;设计作品的优劣从某种角度来说是设计思维深入程度决定的;设计思维是以个人对世界的认识为基础的;人对世界认识的程度实际上也就是设计思维深入的程度,因此我们应弄清自己思维的渊源,树立正确的世界观。 相似文献
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JM Lundberg A Dahlstr?m A Bylock H Ahlman G Pettersson I Larsson HA Hansson J Kewenter 《Canadian Metallurgical Quarterly》1978,104(1):3-12
The innervation of the duodenal enterochromaffine cells (E.C.) of the guinea pig was studied at the electronmicroscopic level. Pretreatment with 5-OH-dopamine was performed to visualize catecholaminergic (CA) nervous elements. Near the basement membrane of all examined E.C. in the crypts, bundles of unmyelinated nerve processes were observed, only partly ensheathed in a Schwann cell cover. At least 4 types of processes could be observed. 1) Boutons containing only small clear vesicles, probably cholinergic fibres; 2) boutons with small clear vesicles, and in addition large (greater than 200 nm) granules with a dense matrix (P-type-fibres); 3) boutons with small electron-dense vesicles, probably CA-fibres; and 4) processes with few vesicles but having the appearance of dendrites. No typical synaptic arrangements were observed, but the minimal distance between the E.C. and the nerve bundles was 150 to 250 nm, thus well within the functional limits of the "autonomic gap". Thus epithelial E.C. may be influenced by several types of nervous elements, including CA-fibres. 相似文献
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HA Kühn 《Canadian Metallurgical Quarterly》1977,107(15):514-520
There is as yet no specific treatment for viral hepatitis, and in an uncomplicated course no further action apart from moderate bedrest is necessary. The patient should however, be isolated in a special ward. In fulminant hepatic failure the benefit of glucocorticoid therapy is still controverted and appears to depend on an early beginning. Treatment with HBsAg-rich human serum in fulminant hepatitis B is still under evaluation. In chronic active hepatitis the administration of azathioprine in combination with glucocorticoids is highly effective, and it appears to be irrelevant whether HBsAg is present in plasma or not; however, the best results have been achieved in "lupoid" hepatitis. The use of transfer factor, laevamisol or thymosin to suppress T-cell action on antibody production of the B-cells cannot yet be finally evaluated with respect to its effectiveness in chronic active hepatitis. Prevention is of major importance in solving the problems involved in hepatitis B infections. Recent experience with active immunization using HBsAg-rich sera or purified formalin inactivated HBsAg preparations suggest the possibility of successful vaccination against hepatitis B in the near future, but the precondition for obtaining sufficient quantities of vaccine is to find suitable culture media for the virus. 相似文献
79.
In this paper we investigate the relation between architectural support for Prolog and performance. We will show that partial support for tags does perform as well as full support, but it only reduces the execution time by approximately 10%. With respect to special addressing modes, auto address modification (post/pre increment, decrement on loads and stores) only yields a cycle reduction of approximately 6% and the introduction of a single shadow register set yields around 8%. Combining these optimizations, a performance gain of 20 to 25% can be achieved, depending on the memory system. Usingvliw techniques, which exploit instruction-level parallelism, the performance can be doubled, using three processing elements. Two processing elements already provide a significant speedup, but the use of four processing elements is not justified if we compare the gain in performance with the cost of the extra hardware. In general we observe only a small performance improvement (around 20%) when moving fromrisc to special-purposerisc architectures, an improvement which can also be achieved by applying advanced compiler technology, such as compiler optimization, optimizations forwam, and optimal scheduling techniques forvliw architectures. Unfortunately these hardware and software effects do not add up, as a better compiler reduces the effect of hardware support. Finally, the cycle time is essential for comparing the performance of different (micro)-architectures, but it is not always clear what the effects of the different tradeoffs are on the maximum achievable cycle time. 相似文献
80.