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排序方式: 共有4986条查询结果,搜索用时 15 毫秒
91.
K. Hamioud V. Arnal V. Jousseaume B. Icard S. Manakli G. Imbert M. Assous D. Galpin J. Guillan E. Richard M. Haond 《Microelectronic Engineering》2010,87(3):316-320
A 32 nm node BEOL integration scheme is presented with 100 nm metal pitch at local and intermediate levels and 50 nm via size through a M1-Via1-M2 via chain demonstrator. To meet the 32 nm RC performance specifications, extreme low-k (ELK) porous SiOCH k = 2.3 is introduced at line and via level using a Trench First Hard Mask dual damascene architecture. Parametrical results show functional via chains and good line resistance. Integration validation of ELK porous SiOCH k = 2.3 is investigated using a multi-level metallization test vehicle in a 45 nm mature generation. 相似文献
92.
Takamitsu Kurita 《时间序列分析杂志》2011,32(6):672-679
This note investigates local power properties of likelihood‐based cointegrating rank tests for partial and full vector autoregressive systems. The asymptotic distributions of partial likelihood‐based tests under local alternatives are derived, depending on various specifications of deterministic terms. A simulation study is then performed using both the full and partial systems. It is demonstrated that the rank tests based on the partial system, if a required parametric condition is fulfilled, can be more powerful than those based on the full system. This finding encourages testing cointegrating rank using a partial system as well as a full system, in such circumstances as the parametric condition could be satisfied. 相似文献
93.
STM32F4系列抢占Cortex-M4内核先机 总被引:2,自引:0,他引:2
Cortex-M4是ARM最新的嵌入式处理器,用以满足有效且易于使用的控制和信号处理功能混合的数字信号控制市场。日前,ST(意法半导体宣布其基于Cortex-M4内核的微控制器(MCU)-STM32F4系列产品正式上市。作为STM32平台的新产品,STM32F4系列提高了运行速度,并增加了信号处理功能。 相似文献
94.
Mohammad Reza Farzanegan 《Energy Economics》2011,33(6):1055-1069
Oil revenues play an important role in the political economy of Iran. On average, 60% of the Iranian government revenues and 90% of export revenues originate from oil and gas resources. Current international sanctions on Iran have mainly targeted the oil production capacity of Iran and its exports to the global markets. In this study, we analyze the dynamic effects of oil shocks on different categories of the Iranian government expenditures from 1959 to 2007, using impulse response functions (IRF) and variance decomposition analysis (VDC) techniques. The main results show that Iran's military and security expenditures significantly respond to a shock in oil revenues (or oil prices), while social spending components do not show significant reactions to such shocks. 相似文献
95.
96.
三十二式太极剑是高等院校体育教学的重要组成部分,对促进大学生身心健康发展有极其重要的作用。为推动高等院校太极剑教学的发展,培养学生的终身体育意识。本文从三十二式太极剑教学的角度,探索分析太极剑的教学方法,以达到提高三十二式太极剑教学效果的目的。 相似文献
97.
Grain boundaries in thin Bi(1 1 0) films deposited on highly oriented pyrolytic graphite are investigated at atomic resolution using scanning tunnelling microscopy and high-resolution transmission electron microscopy. We find preferred misorientation angles Θ equal to 216°, 87°, 49°, 31°, 20°, 12° and 5°, the majority of which can be classified as large-angle boundaries. We find good agreement between the experimental results and a model of the tilt [1 1 0] grain boundary developed here. A method for estimating the surface unit cell based on measurement of dihedral angle in low-resolution images is also developed. 相似文献
98.
To increase the fractional energy savings achieved with solar thermal combisystems the store volume may be increased. Installation of large stores in single-family houses is, however, often limited by space constraints. In this article the influence of the store dimensions, as well as internal and external auxiliary volume configurations, are investigated for large solar water stores by annual dynamic TRNSYS simulations. The results show that store sizes up to 4 m3 may be used in solar heating systems with 30 m2 collector area. It is further shown that well-insulated stores are rather insensitive to the geometry. Stores deviating from the conventional dimensions still yield high fractional energy savings. Furthermore, the simulations show that the performance of an internal auxiliary volume configuration in most cases exceeds that of a solution with an external auxiliary unit. The practical limitations of very thin auxiliary volumes must, however, be further investigated. 相似文献
99.
N. Borisenko E. Zschippang S. Zein El Abedin A. Bund F. Endres 《Electrochimica acta》2009,54(5):1519-5
The electroreduction of 0.5 M TaF5 on Au(1 1 1) and on polycrystalline gold substrates was investigated at room temperature in the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide, [Py1,4]TFSA, by cyclic voltammetry, in situ scanning tunneling microscopy (STM) and electrochemical quartz crystal microbalance (EQCM). The electrochemical reduction of TaF5 in the employed ionic liquid occurs in several steps. The first redox process is attributed to the reduction of TaF5 to TaF3, which likely occurs in the solution, as EQCM indicates no mass change. The electrodeposition of tantalum occurs only in a very narrow potential window and is preceded by the formation of various non-stoichiometric tantalum subhalides. Attempts to deposit micrometer thick tantalum layers at room temperature fail, presumably because of kinetic reasons. 相似文献
100.
Kenta Arima Katsuyoshi Endo Toshihiko Kataoka Kikuji Hirose Hidekazu Goto Yasushi Oshikane Haruyuki Inoue Yoshitaka Tatara Yuzo Mori 《Computational Materials Science》1999,14(1-4):236-240
Local density of states (LDOS) is obtained by the first principles calculation based on the density functional theory on the Si(0 0 1)2 × 1 surface and on the surface with an Al dimer. At an Al dimer, LDOS has a high intensity in the conduction band region, which cannot be seen on the Si(0 0 1)2 × 1 surface. This tendency is observed in STS measurements as well. The possibility for a microelementary analysis is presented by applying this method to other metal atoms on the Si surface. Furthermore, it is pointed out that STS measurements should be always performed at the same tip-sample separation to obtain reproducible STS spectrums. 相似文献