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71.
This paper reports practical experience in implementing Alice, an extension of Standard ML, on top of an existing implementation of Oz. This approach yields a high-quality implementation with little effort. The combination is an advanced programming system for both Oz and Alice, which offers more than either language on its own.Many thanks go to Ulrike Becker-Kornstaedt, Thorsten Brunklaus, Tobias Müller, and Christian Schulte for their comments on a previous version of this paper. For the numerous discussions regarding the details of the translation scheme, thanks go to Andreas Rossberg, implementor of the Alice compiler frontend. Finally, I'd like to thank the anonymous referees for their commments. 相似文献
72.
73.
Novel test circuits for the accurate determination of soft error rate (SER) dependency on critical charges QCRIT have been developed. The minimum charge necessary for flipping the state of a sensor cell, denoted by QCRIT, is measured with 1%-2% accuracy before exposing the circuits to radiation. During the accelerated testing, circuits biased with multiple different supply voltages VCC are simultaneously placed into a beam and any bit flips are logged. From the measured SER dependency on VCC and previously measured QCRIT dependency on VCC, the dependency of SER on QCRIT can be deduced by correlating VCC's for the two measurements. Furthermore, the sensor cell utilizes a single dynamic node which can be programmed to detect strikes on either N- or P-type diffusions, but not both at the same time. The measured dependency SER(QCRIT), normalized by the diffusion area, can be used for predicting SER of any other circuit fabricated in the same process and aid designers in optimization for reduced SER. Predictions of a theoretical SER model, if one is available, can be compared directly with the measurements. Since the true QCRIT of the test circuits is known accurately, any discrepancy larger than given by the measurement uncertainty of SER(QCRIT) would be clearly due to limitations of the SER model. We implemented the test circuits in a 0.6-μm bulk CMOS process and verified accuracy of QCRIT(VCC) calibration method 相似文献
74.
Adaptive QRS Detection: A Study of Performance 总被引:2,自引:0,他引:2
Sornmo Leif Paklm Olle Nygards Mats-Erik 《IEEE transactions on bio-medical engineering》1985,(6):392-401
QRS detectors are often evaluated in terms of statistical measures, e.g., rate of false and true detections. These measures are usually calculated for a detector with fixed parameter values. In this paper, detector properties are studied by varying those parameters which seem to have the most profound effect on performance. By applying techniques known from optimal estimation to a stochastic model for the ECG, two different detectors have been derived. The detector structures are described in detail. In order to study and compare the performance of the two detectors, a database of "difficult" ECG's has been collected, containing various "artifacts" of physiological and electrical/mechanical origin. The performance of this database is presented in terms of receiver-operating characteristics (ROC's), and several examples are discussed. 相似文献
75.
3-Halobithienyls have been prepared through the Pd(PPh3)4-catalyzed coupling of thiopheneboronic acids with 2,4-dihalothiophenes. The ring-opening of the corresponding 3-lithiobithienyls obtained upon halogen-metal exchange with phenyllithium has been investigated. Compound 12 , 3′-iodo-2,2′,2″-terthienyl, was prepared in one step through the Pd(PPh3)4-catalyzed coupling of two equivalents of 2-thiopheneboronic acid with 2,3,5-triiodothiophene. Treatment of 12 with phenyllithium and methyl iodide gave a mixture of compounds 10 and 11 occurring in Berkheya and Cullumia species. 相似文献
76.
77.
Simon M. M. Pedersen Caroline Nebel Niels Chr. Nielsen Henrik J. Andersen Johan Olsson Magnus Simrén Lena Öhman Ulla Svensson Hanne C. Bertram Anders Malmendal 《European Food Research and Technology》2011,233(6):1013-1021
In the present study, the use of gas chromatography mass spectrometry (GC–MS)-based metabonomics to characterize blood serum
in an intervention study of patients suffering from the common gastrointestinal disorder irritable bowel syndrome (IBS) was
investigated. The patients included in the study consumed an acidified milk product with (n = 30) or without probiotics (n = 31) (Lactobacillus paracasei F19, Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12) for an 8-week period, and blood serum samples were collected before and after the intervention. Acidified milk is
commonly used as a delivering vector for probiotics in commercial consumer settings. The serum samples were extracted and
derivatized using N-Methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), and GC–MS analysis was carried out. Multivariate data analysis including principal
component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), and S-plot was applied on the
obtained GC–MS data, which revealed higher serum lactate, glutamine, proline creatinine/creatine, and aspartic acid levels
and lower serum glucose levels after the intervention period for both treatment groups. Consequently, the present study indicated
an effect of acidified milk consumption on the plasma metabolite profile, which was independent of a concomitant intake of
probiotics. In addition, the present study demonstrates that GC–MS is a useful analytical technique for metabonomics studies
of blood serum. 相似文献
78.
In this paper, the small-signal performance of different vector controllers for grid-connected voltage-source converters is investigated. Losses in the line filter, as well as nonlinearities due to blanking time and nonideal valves, are usually not modeled in the evaluation of the performance of control principles. A method to compensate for nonlinearities due to blanking time and nonideal valves is implemented. Furthermore, the influence of the compensation principle on the performance of traditional deadbeat controllers is shown in measured frequency responses. The compensation method reduces the cross-coupling gain and improves the direct-coupling gain. To show the influence of nonlinearities, measured frequency responses are compared with responses obtained from analytical models. At high frequencies, the frequency-dependent losses in the line filter should be taken into account to predict the dynamic performance correctly 相似文献
79.
Lund University, Sweden, is developing a video analysis system for making long-term behavioural studies, primarily in complex urban environments. Road users are detected using the KLT (Kanade-Lucas-Tomasi) interest point tracker. Trajectories are estimated using foreground-background segmentation, whereas speed is estimated using the shape analysis of interest points. The extracted trajectories are further used for behavioural analysis. The authors present the experience from an ongoing study in Stockholm city, where the task was to find out if allowing two-way bicycle traffic on one-way streets had negative effects on safety. The video analysis system was applied to detect biking in the -wrong- direction and analyse traffic conflicts between cyclists and other road users. The manual observations done in parallel allowed validating the accuracy of system performance. 相似文献
80.
Francesca Giuffrida Frédéric Destaillats Maria Herrero Egart Bernadette Hug Pierre-Alain Golay Leif H. Skibsted Fabiola Dionisi 《Food chemistry》2007,101(3):1108-1114
Heat flux differential scanning calorimetry (DSC) and electron spin resonance spectroscopy (ESR) were used to assess the activity and the thermal stability of antioxidants in four vegetable oils. Sunflower oil (SO) and high oleic sunflower oil (HOSO), both rich in diunsaturated fatty acids (FA), low trans oil (LT) and partially hydrogenated palm oil (PHPO), both containing monounsaturated FA, were analyzed by isothermal heat flux DSC, with or without 300 mg/kg of antioxidant: ascorbyl palmitate (AP), α-tocopherol (αT), δ-tocopherol (δT) and propyl gallate (PG). DSC experiments showed that δT is the most effective antioxidant for SO and PG for the less unsaturated oils. SO and PHPO were also analyzed by ESR at 120 and 145 °C, respectively. ESR results confirm the strongest antioxidant activity of δT and PG for SO and PHPO, respectively. Therefore, the present study demonstrates that DSC and ESR are valuable technologies to study activity and stability of antioxidants at high temperature. Moreover, experiments performed in the presence of the spin-trap N-tert-butyl-α-phenylnitrone (PBN), suggest that δT delay lipid oxidation through a different reaction mechanism when compared to αT. A different mechanism between tocopherols isomers in delaying lipid oxidation has been hypotized. 相似文献