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141.
We consider the incompressible Navier–Stokes equations with spatially periodic boundary conditions. If the Reynolds number is small enough we provide an elementary short proof of the existence of global in time Hölder continuous solutions. Our proof uses a stochastic representation formula to obtain a decay estimate for heat flows in Hölder spaces, and a stochastic Lagrangian formulation of the Navier–Stokes equations. 相似文献
142.
Brungart DS Iyer N Simpson BD 《The Journal of the Acoustical Society of America》2006,119(4):2327-2333
When listening to natural speech, listeners are fairly adept at using cues such as pitch, vocal tract length, prosody, and level differences to extract a target speech signal from an interfering speech masker. However, little is known about the cues that listeners might use to segregate synthetic speech signals that retain the intelligibility characteristics of speech but lack many of the features that listeners normally use to segregate competing talkers. In this experiment, intelligibility was measured in a diotic listening task that required the segregation of two simultaneously presented synthetic sentences. Three types of synthetic signals were created: (1) sine-wave speech (SWS); (2) modulated noise-band speech (MNB); and (3) modulated sine-band speech (MSB). The listeners performed worse for all three types of synthetic signals than they did with natural speech signals, particularly at low signal-to-noise ratio (SNR) values. Of the three synthetic signals, the results indicate that SWS signals preserve more of the voice characteristics used for speech segregation than MNB and MSB signals. These findings have implications for cochlear implant users, who rely on signals very similar to MNB speech and thus are likely to have difficulty understanding speech in cocktail-party listening environments. 相似文献
143.
Saijyothi AV Angayarkanni N Syama C Utpal T Shweta A Bhaskar S Geetha IK Vinay PS Thennarasu M Sivakumar RM Prema P 《Electrophoresis》2010,31(20):3420-3427
Tear proteomics, by 2-DE, can give a fingerprint of the protein profile, which is well suited in clinical proteomics for biomarker identification and in diagnostics. The mode of tear collection can influence the representation of the proteins in the tear and therefore it is important to use the appropriate method. In this study, capillary and Schirmer mode of tear collection was done in the healthy controls and the Schirmer method was validated in dry eye syndrome conditions. 2-D PAGE of normal and dry eye tear was performed using pH 3-10 linear IPG strips followed by 13% SDS-PAGE. The spot intensity was analyzed by the PD quest software. The two methods were compared using Bland-Altman statistical tool. The 2-D map of capillary and Schirmer tear showed 147 ± 8 spots and 145 ± 7 spots respectively. Both the collection methods were in agreement with each other and were comparable. Dry eye tear protein showed differential expression of proteins as observed in 25-35 kDa region. One of the significantly reduced protein was identified as proline-rich 4 protein. Schirmer method of tear collection is reliable in patients with dry eye, which can display the differential protein expression and help in biomarker identification. 相似文献
144.
Werner S Iyer PS Fodor MD Coleman CM Twining LA Mitasev B Brummond KM 《Journal of combinatorial chemistry》2006,8(3):368-380
The solution-phase synthesis of a discovery library of 178 tricyclic pyrrole-2-carboxamides was accomplished in nine steps and seven purifications starting with three benzoyl-protected amino acid methyl esters. Further diversity was introduced by two glyoxaldehydes and 41 primary amines. The combination of Pauson-Khand, Stetter, and microwave-assisted Paal-Knorr reactions was applied as a key sequence. The discovery library was designed with the help of QikProp 2.1, and physicochemical data are presented for all pyrroles. Library members were synthesized and purified in parallel and analyzed by LC/MS. Selected compounds were fully characterized. 相似文献
145.
J. N. Sharma P. M. Sakhalkar K. S. Iyer U. R. Marwah 《Journal of Radioanalytical and Nuclear Chemistry》1999,240(3):959-961
The potentiometric estimation of D2EHPA containing M2EHPA of various samples in reagent grade acetone was studied. The differential
plot of the results of analysis were determined using ORIGIN mathematical software for end point determination. Visual color
indicators were also tested for estimation of D2EHPA and M2EHPA, but the accuracy of measurement was less than the endpoint
determination by differential plots. 相似文献
146.
Krishna B. Athreya Siva R. Athreya Srikanth K. Iyer 《Proceedings Mathematical Sciences》2010,120(3):363-385
This paper studies: (i) the long-time behaviour of the empirical distribution of age and normalized position of an age-dependent
critical branching Markov process conditioned on non-extinction; and (ii) the super-process limit of a sequence of agedependent
critical branching Brownian motions. 相似文献
147.
This paper describes the reliability MicroKernel (RMK) framework, a loadable kernel module (or a device driver) for providing application-aware reliability, and dynamically configuring reliability mechanisms. Characteristics of application/system execution are exploited transparently through application-aware reliability techniques to achieve low-latency detection, and low-overhead checkpointing. The RMK prototype is implemented in both Linux, and Windows; and it supports detection of application/OS failures, and transparent application checkpointing. Experiment results show that the system hang detection and application hang detection, which exploit characteristics of application, and system behavior, can achieve high coverage (100% observed in our experiments) with a low false positive rate. Moreover, the performance overhead of RMK, and its detection/checkpointing mechanisms, is small: 0.6% for application hang detection, and 0.1% for transparent application checkpointing in the experiments. 相似文献
148.
149.
Kirihata T. Parries P. Hanson D.R. Hoki Kim Golz J. Fredeman G. Rajeevakumar R. Griesemer J. Robson N. Cestero A. Khan B.A. Geng Wang Wordeman M. Iyer S.S. 《Solid-State Circuits, IEEE Journal of》2005,40(6):1377-1387
An 800-MHz embedded DRAM macro employs a memory cell utilizing a device from the 90-nm high-performance technology menu; a 2.2-nm gate oxide 1.5 V IO device. A concurrent refresh mode is designed to improve the memory utilization to over 99% for a 64 /spl mu/s data retention time. A concurrent refresh scheduler utilizes up-count and down-count registers to identify at least one array to be refreshed at every clock cycle, emulating a classical distributed refresh mode. A command multiplier employs low frequency phased clock signals to generate the clock, commands, and addresses at rates up to 4/spl times/ that of the tester frequency. The macro integrates masked redundancy allocation logic during at speed multibank test. The hardware results show a 312-MHz random access frequency and 800-MHz multibank frequency at 1.2 V, respectively. 相似文献
150.
Rare earth element (REE) concentrations in United States Geological Survey (USGS) rock standards AGV-1, GSP-1, G-2 and PCC-1 were determined by isotope dilution mass spectrometry (IDMS), neutron activation and inductively coupled argon plasma atomic emission spectrometric techniques. The procedure involved acid digestion of samples in PTFE pressure bombs and group separation of REEs by an ion-exchange method. For IDMS an additional separation step using α-hydroxyisobutyric acid as an eluent was used in a cation-exchange column to split the REEs into subgroups. Comparison of the results with literature values showed that the IDMS values are the most precise and accurate. However, the precisions and the accuracies of the other techniques are acceptable. 相似文献