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111.
112.
In this paper, we investigate various ways of characterizing words, mainly over a binary alphabet, using information about the positions of occurrences of letters in words. We introduce two new measures associated with words, the position index and sum of position indices. We establish some characterizations, connections with Parikh matrices, and connections with power sums. One particular emphasis concerns the effect of morphisms and iterated morphisms on words.  相似文献   
113.
Ultra short pulsed laser deposition technique was utilized to create amorphous diamond, alumina and carbon nitride, and two different titania coatings on silicon wafers, thus producing five different surface deposited films with variable physico-chemical properties. The surface characterizations, including the roughness, the contact angle and the zeta potential measurements were performed before we tested the growth properties of human osteoblast-like Saos-2 cells on these surfaces (three separate experiments). The average roughness and hydrophobicity were the highest on titania-deposited surfaces, while carbon nitride was the most hydrophilic one. Osteoblasts on all surfaces showed a flattened, spread-out morphology, although on amorphous diamond the cell shape appeared more elongated than on the other surfaces. On rough titania, the area covered by the osteoblasts was smaller than on the other ones. Cell proliferation assay did not show any statistically significant differences.  相似文献   
114.
The influence of direct water injection (DWI) on emissions from a multivariable large-scale (6–18 cyl, ~ 1 MW/cyl) diesel engine is reported, using a combined injection valve and nozzle that allows for injection of water and fuel oil into the cylinder. This method allows for injecting a relatively large amount of water without derating the engine power and NOx emissions can be more than halved by DWI. Indeed DWI decreases combustion temperatures and NOx emissions, but it gives somewhat increased (yet not problematic) emissions of CO, HC, soot (smoke) and particulate matter (PM), depending on the water injection timing and degree of incomplete combustion.  相似文献   
115.
A low noise 0.9 GHz FBAR clock consisting of an oscillator and divider circuit for single-sided-to-differential conversion for a high-speed interleaved pipeline A/D-converter was designed, realized with an in-house FBAR and a commercial 0.35 μm CMOS process, and tested. The circuit showed very good jitter and phase noise performance. A temperature coefficient of –47 ppm/K was measured.  相似文献   
116.
Solar cells have been fabricated on n-type and p-type moderately doped Si. The shrinkage of the Si bandgap has been obtained by measuring the internal quantum efficiency in the near infrared spectrum (hv = 1.00?1.25 eV) around the fundamental absorption edge. The results agree with previous optical measurements of bandgap narrowing in Si. It is postulated that this optically-determined bandgap narrowing is the rigid shrinkage of the forbidden gap due to many-body effects. The “device bandgap narrowing” obtained by measuring the pn product in bipolar devices leads to discrepant values because (i) the density of states in the conduction and valence band is modified due to the potential fluctuations originated in the variations in local impurity density, and (ii) the influence of Fermi-Dirac statistics.  相似文献   
117.
The paper investigates infinite words, and sets of them, associated with DOL and DTOL systems. Main emphasis is on characterization and decidability results.  相似文献   
118.
The design and life prediction of fretting wear-sensitive mechanical components remain a challenge. In the present work, the role of wear particle movements under conditions of axisymmetric loading of an annular flat-on-flat contact were investigated using self-mated quenched and tempered steel specimens. Total fretting wear significantly increased when loose wear particles were periodically removed from the interface, and this effect increased as a function of the sliding amplitude. Additionally, increased wear was measured when grooves perpendicular to the sliding direction were added to the interface. Increasing the rate of wear debris ejection leads to increased wear rate because naturally occurring entrapped third-body particles significantly reduce the wear. The shape of fretting loops and values of the average and maximum coefficient of friction remained unaffected by the removal of entrapped wear debris and by the introduction of the grooves.  相似文献   
119.
Delivery truck drivers’ work contains various physically and psychosocially demanding work situations. Fifteen drivers’ and 8 other stakeholders’ identifications of such work situations were examined by video analyses in this study. The identifications were analyzed in‐depth by the researchers and compared with statistics on 3,507 accidents in the Finnish trucking industry. The aim was to determine what kind of identifications were made and to what degree the identifications coincided among the participants and with the accident statistics. The drivers’ identifications differed from the statistics data. The statistics showed a significantly higher relative frequency of movement‐related situations. However, the identifications also included risks for future workload‐related musculoskeletal disorders. Most commonly, these were emphasized during manual materials handling. The participation of different interest groups seems to increase the amount of relevant information obtained. Nonetheless, the age of the evaluator seems not to affect the analyses.  相似文献   
120.
As people own more and more various smart devices, providing advertising to those devices has become a lucrative platform for different advertisement providers. However, the way advertisements are delivered to customers' smart devices needs to be improved. Many variables determine the most effective way to provide the mobile advertisement to the end-user. So a mobile advertising service based on the 4R model is needed The correct time, location, contents and target device to make the mobile advertising interesting and also useful for the customers. need to be determined in order for the advertisement to be contextual and the most effective. The 4R model is beneficial for the advertisers and the end-users alike.  相似文献   
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