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941.
The authors describe a 9.02×9.02-mm chip built in 1-μm CMOS with two levels of metal and an additional mask level for fabricating capacitors. It contains both analog and digital circuits and has provisions for self-test. The function includes the transmitter, receiver, protocol handler, an microprocessor, as well as interfaces for RAM/ROM storage, IBM PC bus, IBM PS/2 bus, IBM 3174 bus, and Motorola 68000 bus. The physical design terrains are formed by 24K circuits of standard cell gates, a 10K-circuit equivalent hand-honed custom microprocessor, and an analog macro. The chip operates from a single 5-V supply, and the power consumption is 0.8 W nominal at 16 Mb/s. The chip can also be operated at 4 Mb/s  相似文献   
942.
The effects of adding sodium hydroxide (NaOH), separately or in combinastion with various inorganic phosphates, on meat emulsion characteristics were studied. In comparing the addition of either NaPP or NaOH, 0.075% NaOH resulted in a higher raw emulsion pH and greater solubilized protein than 0.30% NaPP, but NaPP resulted in a more stable emulsion. The combination of 0.075% NaOH and 0.30% NaPP resulted in a soluble protein level less than when the ingredients were added individually and only slightly higher than if neither were present. The addition of NaOH (at 1 part NaOH to 4 parts phosphate) decreased cooked yields. With NaAPP and NaPP, NaOH reduced yields below that of the control.  相似文献   
943.
A study was made of the effect of wheat bran contained by the antisclerotic diet on lipid metabolism in patients with chronic coronary heart disease. Eighty-two patients (males) aged 36-59 years with a history of myocardial infarction of 1- to 15 year-standing were entered into the study. It was ascertained that inclusion into the antisclerotic diet of wheat bran in an amount of 70-80 g does not exert any hypolipidemic action. No elevation of the serum alpha-cholesterol content was noticed either. The augmentation of the cholic acid concentration together with a reduction in the cholesterol content in the hepatic bile attests to its reduced lithogenicity.  相似文献   
944.
Water photolysis has been studied in liquid phase, using neutral aqueous suspensions of RuOx/Pt/TiO2 particles and u.v. light. A continuous gas flow apparatus of ca 350 cm3 of total volume and holding 150 cm3 of catalyst suspension was designed and tested. Hydrogen generation rates up to 110 μmol h?1 have been obtained. Influence of photoproducts and catalyst concentration on the process rate is studied. Discussion is centred in the role played by oxygen in catalyst activity and process dynamics.  相似文献   
945.
The initial problems associated with the fieldwork and integration of the results of four independent European university research groups involved in magnetotelluric studies in the Travale Test Site are discussed. This is followed by an account of the development of collaborative field studies, rewarding data and computer programme interchange and finally compatibility in the resulting electrical conductivity models and their interpretation. A suggested strategy for future EEC collaborative geothermal studies concludes this overview.  相似文献   
946.
947.
948.
Bilateral control of teleoperators with time delay   总被引:5,自引:0,他引:5  
A control law for teleoperators is presented which overcomes the instability caused by time delay. By using passivity and scattering theory, a criterion is developed which shows why existing bilateral control systems are unstable for certain environments, and why the proposed bilateral control law is stable for any environment and any time delay. The control law has been implemented on a single-axis force-reflecting hand controller, and preliminary results are shown. To keep the presentation clear, a single-degree-of-freedom (DOF) linear time-invariant (LTI) teleoperator system is discussed. Nevertheless, results can be extended, without loss of generality, to an n-DOF nonlinear teleoperation system  相似文献   
949.
A monolithic grating surface-emitting, GaAs/AlGaAs, separate-confinement-heterostructure, single-quantum-well diode laser has been fabricated on a Si substrate using a single-step metalorganic chemical vapour deposition process. An output power of 30 mW has been obtained under pulsed operation with a peak emission wavelength of 885 nm.<>  相似文献   
950.
In this paper, we propose a cognitive cellular system based on DS MC-CDMA to coexist with a number of narrow-band legacy systems in the same frequency range. If the bandwidth and the frequency location of each narrow-band system are known to this cognitive MC-CDMA, it is possible to mitigate their interfering effect in the cognitive receivers by adaptive transmission. We will develop an algorithm for calculating the adaptive transmission parameters and show that it combats interference in the channel effectively.  相似文献   
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