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71.
Pradeep K. Nalla Roland J. Weiss Prakash Peranandam Jürgen Ruf Thomas Kropf Wolfgang Rosenstiel 《Electronic Notes in Theoretical Computer Science》2006,135(2):47
In this paper we describe an algorithm for distributed, BDD-based bounded property checking and its implementation in the verification tool SymC. The distributed algorithm verifies larger models and returns results faster than the sequential version.The core algorithm distributes partitions of the state set to computation nodes after reaching a threshold size. The nodes proceed with image computation on the nodes asynchronously. The main scalability problem of this scheme is the overlap of state set partitions. We present static and dynamic overlap reduction techniques. 相似文献
72.
73.
H. -J. Weiss 《Journal of Materials Science》1977,12(4):797-809
The effect of axial residual stress on the properties of continuous fibre composites is calculated. It is emphasized that composite strength should be considered as a more complex phenomenon than usually done so by merely considering ultimate strength. It is shown that the information contained in ()-curves if plotted in a more suitable form as hysteresis and set versus total strain, taking into account residual stress, may be a useful means for characterizing the composite and for detecting deviations from perfect structure. Conclusions are derived as to how composite performance may be improved. The results are substantiated by metallic composite data. 相似文献
74.
Josef Widder Martin Biely Günther Gridling Bettina Weiss Jean-Paul Blanquart 《Distributed Computing》2012,24(6):299-321
We consider the problem of reaching agreement in distributed systems in which some processes may deviate from their prescribed
behavior before they eventually crash. We call this failure model “mortal Byzantine”. After discussing some application examples
where this model is justified, we provide matching upper and lower bounds on the number of faulty processes, and on the required
number of rounds in synchronous systems. We then continue our study by varying different system parameters. On the one hand,
we consider the failure model under weaker timing assumptions, namely for partially synchronous systems and asynchronous systems
with unreliable failure detectors. On the other hand, we vary the failure model in that we limit the occurrences of faulty
steps that actually lead to a crash in synchronous systems. 相似文献
75.
Rotheram-Borus Mary Jane; Weiss Robert; Alber Susan; Lester Patricia 《Canadian Metallurgical Quarterly》2005,73(2):221
The impact of HIV-related parental death on 414 adolescents was examined over a period of 6 years. The adjustment of bereaved adolescents was compared over 4 time periods relative to parental death and was also compared with the adjustment of nonbereaved adolescents. Bereaved adolescents had significantly more emotional distress, negative life events, and contact with the criminal justice system than nonbereaved youths; these behaviors did not remain significantly higher after parental death. Depressive symptoms and passive problem solving increased soon after parental death, as compared with nonbereaved adolescents. One year subsequent to parental death, depression and passive problem solving were similar to the levels of nonbereaved peers. Only sexual risk behaviors increased following parental death. These results suggest the importance of early family intervention soon after parental HIV diagnosis, prior to parental death, and sustained over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Carver Charles S.; Smith Roselyn G.; Antoni Michael H.; Petronis Vida M.; Weiss Sharlene; Derhagopian Robert P. 《Canadian Metallurgical Quarterly》2005,24(5):508
In considering well-being among survivors of life-threatening illnesses such as breast cancer, 2 important questions are whether there is continuity between initial adjustment and longer term adjustment and what role personality plays in long-term adjustment. In this research, a sample of 163 early stage breast cancer patients whose psychosocial adjustment was first assessed during the year after surgery completed the same measures 5-13 years after surgery. Initial reports of well-being were relatively strong predictors of follow-up well-being on the same measures. Initial optimism and marital status also predicted follow-up adjustment, even controlling for earlier adjustment, which exerted a substantial unique effect in multivariate analyses. In contrast, initial medical variables played virtually no predictive role. There is substantial continuity of subjective well-being across many years among survivors of breast cancer, rooted partly in personality and social connection. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Validation of coupled codes using VVER plant measurements 总被引:3,自引:4,他引:3
T. Vanttola A. Hmlinen S. Kliem Y. Kozmenkov F.-P. Weiss A. Keresztúri J. Hdek C. Strmensky S. Stefanova A. Kuchin P. Hlbocky D. Siko S. Danilin 《Nuclear Engineering and Design》2005,235(2-4):507-519
A data set of five transients at different VVER type nuclear power plants was collected in order to validate neutron kinetics/thermal hydraulics codes. Two of these transients ‘drop of control rod at nominal power at Bohunice-3’ of VVER-440 type and ‘coast-down of 1 from 3 working MCPs at Kozloduy-6’ of VVER-1000 type, were then utilised for code validation. Eight institutes contributed to the validation with 10 calculations using 5 different combinations of coupled codes. The thermal hydraulic codes were ATHLET, SMABRE and RELAP5 and the neutron kinetic codes DYN3D, HEXTRAN, KIKO3D and BIPR8. The general behaviour of both the transients was quite well calculated with all the codes. Even an elementary modelling of coolant mixing in reactor pressure vessel under asymmetric transients improved correspondence to the measurements. Some differences between the calculations seem to indicate that fuel modelling and treatment of VVER-440 control rods need further consideration. The simultaneous validation interacted with the data collection effort and thus improved its quality. The complexity of data collection systems and sometimes conflicting data, however, called for compromises and interpretation guides that also taught the analysts balanced plant modelling. 相似文献
78.
L. Ratke S. Steinbach G. Müller M. Hainke J. Friedrich A. Roosz Y. Fautrelle M. D. Dupuoy G. Zimmermann A. Weiss J. Lacaze R. Valdes G -U. Grün H -P. Nicolai H. Gerke-Cantow 《Microgravity science and technology》2005,16(1-4):99-103
The MICAST research program focuses on a systematic analysis of the effect of convection on the microstructure evolution in cast Al-alloys. The experiments within MICAST are carried out under well defined thermally and magnetically controlled, convective boundary conditions and analyzed using advanced diagnostics and theoretical modeling, involving phase field simulation, micro-modeling and global simulation of heat and mass transport. The MICAST team uses as a model material the Al-Si base alloys. This paper gives a brief overview on recent experimental results of the MICAST team on the effect of rotating magnetic fields on microstructure in AlSi alloys. 相似文献
79.
M. Nikolo X. Shi E. S. Choi J. Jiang J. D. Weiss E. E. Hellstrom 《Journal of Superconductivity and Novel Magnetism》2014,27(10):2231-2239
Thermally assisted flux flow (TAFF) based on magneto-resistivity and ac susceptibility measurements is studied in a Ba(Fe0.91Co0.09)2As2(T c=25.3 K) sample in magnetic fields up to 18 T. In addition to the upper critical field μ 0 H c2 and the coherence length ξ(0), the flux flow activation energy U(T,H) has also been determined. The resistive transition width is proportional to μ 0 H, in contrast to Tinkham’s theoretical prediction. By applying Fisher’s model, the glass melting transition temperature T g, which occurs in the upper TAFF state and not in the zero resistivity vortex solid regime, is calculated. The onset of TAFF temperature and the crossover temperature T x from TAFF to flux flow are determined. By contrasting the ac susceptibility data with the resistivity data, considerable flux penetration appears even in the zero resistivity state, in addition to ac losses. The H-T phase diagram is drawn and shows weak pinning regime as the field approaches μ 0 H c2, and the strength of the weak pinning decreases to 0 with increasing magnetic field from 0 to 18 T. 相似文献
80.
Efficient Total Chemical Synthesis of 13C=18O Isotopomers of Human Insulin for Isotope‐Edited FTIR 下载免费PDF全文
Dr. Balamurugan Dhayalan Dr. Ann Fitzpatrick Dr. Kalyaneswar Mandal Dr. Jonathan Whittaker Prof. Dr. Michael A. Weiss Prof. Dr. Andrei Tokmakoff Prof. Dr. Stephen B. H. Kent 《Chembiochem : a European journal of chemical biology》2016,17(5):415-420
Isotope‐edited two‐dimensional Fourier transform infrared spectroscopy (2 D FTIR) can potentially provide a unique probe of protein structure and dynamics. However, general methods for the site‐specific incorporation of stable 13C=18O labels into the polypeptide backbone of the protein molecule have not yet been established. Here we describe, as a prototype for the incorporation of specific arrays of isotope labels, the total chemical synthesis—via a key ester insulin intermediate—of 97 % enriched [(1‐13C=18O)PheB24] human insulin: stable‐isotope labeled at a single backbone amide carbonyl. The amino acid sequence as well as the positions of the disulfide bonds and the correctly folded structure were unambiguously confirmed by the X‐ray crystal structure of the synthetic protein molecule. In vitro assays of the isotope labeled [(1‐13C=18O)PheB24] human insulin showed that it had full insulin receptor binding activity. Linear and 2 D IR spectra revealed a distinct red‐shifted amide I carbonyl band peak at 1595 cm?1 resulting from the (1‐13C=18O)PheB24 backbone label. This work illustrates the utility of chemical synthesis to enable the application of advanced physical methods for the elucidation of the molecular basis of protein function. 相似文献