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81.
This study reexamines the news priming effects of the 1991 Persian Gulf War. Suggesting an alternative approach to those used in previous studies, this study assesses individuals' use and disuse of a contextual prime (i.e., the air war) in dynamic news environments. With a short-term, quasi-experimental approach considering the air war as a prime stimulus, a path analysis suggests robust evidence of the short-term accessibility effects of priming. More importantly, as suggested in Martin's (1986) set/reset model, this study extends priming effects beyond the simple hydraulic patterns of accessibility effects. It reveals that both attitudes toward military action and attitudes toward a diplomatic solution were used in subsequent judgments of the president's job performance and handling of the war. The associations between attitudes toward a diplomatic solution and subsequent judgments were even stronger than those between attitudes toward military action and the same subsequent judgments, despite the clear prowar primes of news discourse in the air-war context. This pattern was more greatly intensified among those in the high news attention group than those in the low news attention group  相似文献   
82.
Fast DCT algorithm with fewer multiplication stages   总被引:1,自引:0,他引:1  
A novel fast DCT scheme with reduced multiplication stages and fewer additions and multiplications is proposed. The proposed algorithm is structured so that most multiplications tend to be performed at the final stage, which reduces the propagation error that could occur in the fixed-point computation. Minimisation of the multiplication stages can further decrease the error  相似文献   
83.
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   
84.
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   
85.
In a high-resolution flat panel system, a conventional interface that directly connects a liquid crystal display (LCD) controller to a flat panel cannot overcome the problems of excess EMI (electromagnetic interference) and power caused by full-swing transmission signals in parallel lines. This paper presents a high-speed digital video interface system implemented with a low-cost standard CMOS (complimentary metal-oxide-semiconductor) technology that can mitigate EMI and power problems in high-resolution flat panel display systems. The combined architecture of the high-speed, small number of parallel lines and low-voltage swing serial interface can support resolutions from VGA (640×480 pixels) up to XGA (1024×768 pixels) with significant power improvement and drastic EMI reduction. To support high-speed, low-voltage swing signaling and overcome channel-to-channel skew problems, a robust data recovery system is required. The proposed digital phase-locked loop enables robust skew-insensitive data recovery of up to 1.04 GBd  相似文献   
86.
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   
87.
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   
88.
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   
89.
A comprehensive Monte Carlo simulator is employed to investigate nonlocal carrier transport in 0.1 μm n-MOSFET's under low-voltage stress. Specifically, the role of electron-electron (e-e) interactions on hot electron injection is explored for two emerging device designs biased at a drain voltage Vd considerably less than the Si/SiO2 injection barrier height φb. Simulation of both devices reveal that 1) although qVdb, carriers can obtain energies greater than φb, and 2) the peak for electron injection is displaced approximately 20 nm beyond the peak in the parallel channel electric field. These phenomena constitute a spatial retardation of carrier heating that is strongly influenced by e-e interactions near the drain edge. (Virtually no injection is observed in our simulations when e-e scattering is not considered.) Simulations also show that an aggressive design based on larger dopant atoms, steeper doping gradients, and a self-aligned junction counter-doping process produces a higher peak in the channel electric field, a hotter carrier energy distribution, and a greater total electron injection rate into the oxide when compared to a more conventionally-doped design. The impact of spatially retarded carrier heating on hot-electron-induced device degradation is further examined by coupling an interface state distribution obtained from Monte Carlo simulations with a drift-diffusion simulator. Because of retarded carrier heating, the interface states are mainly generated further over the drain region where interface charge produces minimal degradation. Thus, surprisingly, both 0.1 μm n-MOSFET designs exhibit comparable drain current degradation rates  相似文献   
90.
Microllular plastics are cellular polymers characterized by cell densities greater than 109 cells/cm3 and cells smaller than 10 μm. One of the critical steps in the continuous production of microcellular plastics is the promotion of high cell nucleation rates in a flowing polymer matrix. These high nucleation rates can be achieved by first forming a polymer/gas solution followed by rapidly decreasing the solubility of gas in the polymer. Since, in the processing range of interest, the gas solubility in the polymer decreases as the pressure decreases, a rapid pressure drop element, consisting of a nozzle, has been employed as a continuous microcellular nucleation device. In this paper, the effects of the pressure drop rate on the nucleation of cells and the cell density are discussed. The experimental results indicate that both the magnitude and the cell density are discussed. The experimental results indicate that both the magnitude and the rate of pressure drop play a strong role in microcellular processing. The pressure phenomenon affects the thermodynamic instability induced in the polymer/gas solution and the competition between cell nucleation and growth.  相似文献   
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