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111.
Tero Laihonen 《Discrete Applied Mathematics》2006,154(17):2499-2510
Fault diagnosis of multiprocessor systems gives the motivation for robust identifying codes. We provide robust identifying codes for the square and king grids. Often we are able to find optimal such codes. 相似文献
112.
We shall show that it is decidable for binary instances of the Post Correspondence Problem whether the instance has an infinite solution. In this context, a binary instance (h,g) consists of two morphisms h and g with a common two element domain alphabet. An infinite solution ω is an infinite word ω=a1a2… such that h(ω)=g(ω). This problem is known to be undecidable for the unrestricted instances of the Post Correspondence Problem. 相似文献
113.
In multi-criteria decision analysis, the overall performance of decision alternatives is evaluated with respect to several, generally conflicting decision criteria. One approach to perform the multi-criteria decision analysis is to use ratio-scale pairwise comparisons concerning the performance of decision alternatives and the importance of decision criteria. In this approach, a classical problem has been the phenomenon of rank reversals. In particular, when a new decision alternative is added to a decision problem, and while the assessments concerning the original decision alternatives remain unchanged, the new alternative may cause rank reversals between the utility estimates of the original decision alternatives. This paper studies the connections between rank reversals and the potential inconsistency of the utility assessments in the case of ratio-scale pairwise comparisons data. The analysis was carried out by recently developed statistical modelling techniques so that the inconsistency of the assessments was measured according to statistical estimation theory. Several type of decision problems were analysed and the results showed that rank reversals caused by inconsistency are natural and acceptable. On the other hand, rank reversals caused by the traditional arithmetic-mean aggregation rule are not in line with the ratio-scale measurement of utilities, whereas geometric-mean aggregation does not cause undesired rank reversals. 相似文献
114.
Tero Tuuttila Manu Lahtinen Noora Kuuloja Juhani Huuskonen Kari Rissanen 《Thermochimica Acta》2010,497(1-2):101-108
Eight Janus-type dendrimers up to the second generation were synthesized, and their thermal properties were evaluated. Compounds consist of the dendritic bisMPA based polyester moieties, and either 3,4-dihexyloxybenzoic acid or 3,4-dihexadecyloxybenzoic acid moieties, attached to opposite sides of the pentaerythritol core. The structures of the molecules were verified with 1H NMR, 13C NMR, ESI TOF mass spectrometry and elemental analysis. The thermal stability was evaluated by thermogravimetric analysis, displaying onset decomposition temperatures (Td) ranging from 241 to 308 °C. Phase transitions were studied by differential scanning calorimetry. Based on the performed studies it was confirmed that OH terminated dendrimers 2, 4, 6 and 8 exhibited liquid crystalline phases. Also, the X-ray powder diffraction measurements were accomplished for the dendrimers having terminal hydroxyl groups. 相似文献
115.
Proper identification of the cable’s resonant frequencies is critical to provide an accurate estimate of cable force. The
MUltiple SIgnal Classification (MUSIC) algorithm is implemented to estimate cable-stayed bridge cable tensions noninvasively from measured
cable motion. This algorithm performs eigenanalysis on the data sequence to estimate and eliminate noise contributions before
creating its frequency spectrum, providing a more robust estimation approach than traditional Fourier based frequency spectrums.
To aid in the selection of cable frequencies, a comprehensive finite difference cable model is simulated and compared to the
estimated MUSIC spectrums. 相似文献
116.
The synthesis and structural characterization of new tantalum(V) compounds containing a single hydrazido(I) ligand are reported. Hydrazinolysis of TaCl(NMe2)4 using trimethylsilyl(dimethyl)hydrazine affords the compound TaCl(NMe2)3[N(TMS)NMe2] in essentially quantitative yield. Metathetical replacement of the chloride ligand in TaCl(NMe2)3[N(TMS)NMe2] by LiNMe2 gives the all-nitrogen coordinated compound Ta(NMe2)4[N(TMS)NMe2]. VT 1H NMR studies support the existence of low-energy pathways involving rotation about the Ta–N bonds of the ancillary amido and hydrazido ligands in both hydrazido-substituted compounds. X-ray crystallographic analyses confirm the octahedral disposition about the tantalum metal in TaCl(NMe2)3[N(TMS)NMe2] and Ta(NMe2)4[N(TMS)NMe2] and the presence of an η2-hydrazido(I) ligand. Preliminary data using Ta(NMe2)4[N(TMS)NMe2] as an ALD precursor for the preparation of tantalum nitride and tantalum oxide thin films are presented. 相似文献
117.
For a large class of locally compact semitopological semigroups S, the Stone-Čech compactification β
S is a semigroup compactification if and only if S is either discrete or countably compact. Furthermore, for this class of semigroups which are neither discrete nor countably
compact, the quotient
contains a linear isometric copy of ℓ
∞. These results improve theorems by Baker and Butcher and by Dzinotyiweyi. 相似文献
118.
When plasmodia of the true slime mold Physarum were exposed to unfavorable conditions presented as three consecutive pulses at constant intervals, they reduced their locomotive speed in response to each episode. When the plasmodia were subsequently subjected to favorable conditions, they spontaneously reduced their locomotive speed at the time when the next unfavorable episode would have occurred. This implied the anticipation of impending environmental change. We explored the mechanisms underlying these types of behavior from a dynamical systems perspective. 相似文献
119.
The emission spectra of the lanthanide chelates enable them to act as a donor for several acceptors emitting at different
wavelengths. Fluorescence resonance energy transfer between terbium(III) chelate labeled antibody Fab fragment (donor) and
a 17β-estradiol conjugated to Alexa Fluor 488, 555, 594 or 680 (acceptor) was employed to study the functionality of the terbium(III)
chelate as an efficient donor for several acceptors emitting from green to far-red. During measurement, the sensitized emission
of the acceptor was measured at acceptor specific wavelength. All the tested dyes proved to be efficient acceptors, and they
were successfully used in the competitive homogeneous E2 assay. The highest signal to background ratio and the best assay
performance was obtained with Alexa Fluor 680, due to the very low donor emission background at the far-red area. In addition,
the sensitized emission of both Alexa Fluor 488 and 680 could be measured simultaneously without significant cross talk. 相似文献
120.
Tero Tikka Jussi Ryynänen Kari Halonen 《Analog Integrated Circuits and Signal Processing》2008,54(2):105-111
This paper focuses on the design and measurements of low-noise amplifiers (LNA) targeted for WCDMA base-station applications. In addition, various gain control techniques and the accuracy in noise measurements have been analyzed. Two different LNA designs are presented. Both LNAs can be operated in two gain modes, which are optimized for different base-station configurations. Both designs are implemented using the same 0.25-μm SiGe BiCMOS process, and both designs achieve the NF of 1 dB and IIP3 of ?5 dBm in high gain mode. 相似文献