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51.
The authors propose a new design concept for controlling the deflection of a micro-membrane with the aid of its thickness distribution for realizing a prescribed design in the MEMS. As an example, the authors treat a micro air pump that comprises a micro-membrane. The membrane is actuated by an electrostatic force. The membrane deflects and thus the deflection is influenced by the air pressure and the electrostatic field. This is a highly complicated system. To find out a proper thickness distribution, the authors use the genetic algorithm that is appropriate to reduce the searching space of solution.  相似文献   
52.
The adoption of the sensory odor test will prevail widely in many local self governments in Japan in order to evaluate and regulate the complex odor in fields. This is also done by the tri‐angle choice bag test. However, this procedure has several problems in the reliability and reproducibility of the results obtained. It is desired to solve these problems by the mechanization of the method. From this point of view, an experimental study on the flow rate of test odor has been carried out and the results obtained are described in this paper. It is confirmed that the optimum flow rate of test odor is about 41/min at the inlet of the mask in the dynamic sniffing method.  相似文献   
53.
Supporting both WCDMA with HSDPA and GSM/GPRS/EDGE, the 9.3 times 9.3 mm2 SoC fabricated in triple-Vth 65 nm CMOS, has three CPU cores and 20 separate power domains. Unused power domains can be powered down to reduce the leakage power. Partial clock activation scheme especially focused on music playback scene dynamically stops a PLL and clock trees when not necessary and reduces power consumption from 33.6 mW to 19.6 mW. IP-MMU translates virtual address to physical address for 18 hardware-IPs and virtual address space can be allocated when necessary and can be freed after its operation, reducing external memory by 43 MB. Video performance of D1 (720 times 520) size with 30 frames per second for MPEG/AVC decoding and encoding can be achieved under mixed virtual and physical address usage.  相似文献   
54.
55.
We investigate deformation-induced martensitic transformation behavior in cold-rolled and cold-drawn specimens of type 316 stainless steel. Deformation-induced martensite preferentially nucleates at the twin boundary between the austenite matrix and a deformation twin. In the cold-rolled specimen, martensite formed at the twin boundary has a Kurdjumov–Sachs (K–S) relationship with both the austenite matrix and the deformation twin (“double K–S relationship”). In the cold-drawn specimen, two kinds of deformation twins with different twin planes are typically formed, and therefore deformation-induced martensites are formed where the deformation twin boundaries intersect: martensite thus has an imperfect “triple K–S relationship” with the austenite matrix and the two deformation twins. The complicated crystallographic orientation relationship between austenite and martensite grains strongly restricts the formation of some variants of deformation-induced martensites. Because of the difference in number of nucleation sites in the cold-drawn and cold-rolled specimens, martensitic transformation is more enhanced in the former than in the latter.  相似文献   
56.
Embodied conversational agents (ECAs) are computer-generated, human-like characters that interact with human users in face-to-face conversations. ECA is a powerful tool for representing cultural differences and is suitable for interactive training or edutainment systems. This article presents preliminary results from the development of a culture-adaptive virtual tour guide agent for serving Japanese, Croatian, and general Western users by displaying appropriate verbal and non-verbal behaviors. It is being implemented in Generic ECA Framework, a modular framework for developing ECAs. Dividing the ECA functions into reusable and loosely coupled modules minimizes the effort required to implement additional behavior and facilitates incremental scale up of the system.  相似文献   
57.
Byrdwell WC  Sato H  Schwarz AK  Borchman D  Yappert MC  Tang D 《Lipids》2002,37(11):1087-1092
Most lipid extraction procedures [Folch, J., Lees, M., and Sloane-Stanley, G.H., (1957) A Simple Method for the Isolation and Purification of Total Lipids from Animal Tissues, J. Biol. Chem. 226, 497–509; Bligh, E.G., and Dyer, W.J. (1959) A Rapid Method of Total Lipid Extraction and Purification, Can. J. Biochem. Physiol. 37, 911–917] employ biphasic solvent mixtures designed to dissolve the lipids in an organic phase and remove impurities in an aqueous phase. However, when applying these protocols to biological matrices such as that of the ocular lens, the formation of an emulsion layer between the organic and aqueous phases causes poor reproducibility in extraction yields and gives only a small amount of the lipid-containing chloroform phase. In this study, we quantified phospholipids at each step of the Folch et al. extraction protocol and compared the yield of human and bovine lens phospholipids obtained by the Folch-based approach and a novel monophasic methanol extraction method designed to circumvent the problems associated with biphasic extraction protocols. A monophasic methanol extraction coupled with 31P NMR spectroscopy was found to be the simplest, quickest, and most effective method for quantifying the phospholipid content of the lens.  相似文献   
58.
Uniaxial-process-induced strained-Si: extending the CMOS roadmap   总被引:2,自引:0,他引:2  
This paper reviews the history of strained-silicon and the adoption of uniaxial-process-induced strain in nearly all high-performance 90-, 65-, and 45-nm logic technologies to date. A more complete data set of n- and p-channel MOSFET piezoresistance and strain-altered gate tunneling is presented along with new insight into the physical mechanisms responsible for hole mobility enhancement. Strained-Si hole mobility data are analyzed using six band k/spl middot/p calculations for stresses of technological importance: uniaxial longitudinal compressive and biaxial stress on [001] and [110] wafers. The calculations and experimental data show that low in-plane and large out-of-plane conductivity effective masses and a high density of states in the top band are all important for large hole mobility enhancement. This work suggests longitudinal compressive stress on [001] or [110] wafers and <110> channel direction offers the most favorable band structure for holes. The maximum Si inversion-layer hole mobility enhancement is estimated to be /spl sim/ 4 times higher for uniaxial stress on (100) wafer and /spl sim/ 2 times higher for biaxial stress on (100) wafer and for uniaxial stress on a [110] wafer.  相似文献   
59.
A method is described by which the order of interconnected power systems is reduced. When the system under study is composed of a main system and several subsystems connected to the main system, the method gives an equivalent model to each subsystem with far fewer generators, even when each subsystem is connected to the main system at more than one point. The paper also discusses the data that needs to be sent from each subsystem when it is expressed by a reduced-order equivalent model. A numerical example of a 250-bus and 61-machine system shows that the method is effective and causes no loss of accuracy. Although the proposed method provides an accurate reduced-order model, it is rather time-consuming, because it is based on the linearized dynamic equations of the system, and their eigenvectors are needed. This problem must be solved before practical use of the method can proceed.  相似文献   
60.
Two women with atrial escape-capture bigeminy were reported in whom sinus P waves and escape P waves alternated with each other. Their electrocardiographic findings showed that, during the bigeminal rhythm, 2:1 exit block of sinus impulses associated with entrance block of escape impulses occurred in the sinoatrial junction. Three phenomena are suggested to explain the observations. (1) Seeming bradycardia-dependent sinoatrial exit block may have occurred, probably as a result of phasic changes in vagal tone due to respiration, with decreased vagal tone depressing conductivity in the sinoatrial junction to a greater degree than automaticity in the sinus node. (2) In case 1, type II second-degree entrance block in the sinoatrial junction may have occurred, reflecting the presence of sinus parasystole with incomplete entrance block. (3) Sinus escape also may have occurred, especially in case 2. These phenomena have never been reported before.  相似文献   
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