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91.
V??n?nen Ari; Buunk Bram P.; Kivim?ki Mika; Pentti Jaana; Vahtera Jussi 《Canadian Metallurgical Quarterly》2005,89(2):176
The authors examined esteem enhancement theory and equity theory in explaining the long-term health status of men (n = 178) and women (n = 575). Baseline characteristics were measured in 1990-1993, intimate reciprocity in 1993, and recorded sickness absences for a 9-year period during 1993-2001. Among women, giving more support than receiving in intimate relationships positively affected subsequent health status, as indicated by fewer sickness absences. Among men, receiving more support than giving predicted fewer absences. These effects remained even after significant covariates were included in the model. Thus, women seem to benefit from giving support in intimate relationships, and men seem to benefit from receiving support in intimate relationships. The findings on women are in line with the esteem enhancement theory. No support was obtained for the equity theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
The paper describes a probabilistic method for transmission grid security evaluation. Power system security is the ability of the power system to withstand sudden disturbances such as short circuits. The method presented here uses event and fault trees and combines them with power system dynamic simulations. Event trees model the substation protection and trip operations after line faults. Different event tree end states (fault duration, circuit breaker trips) are simulated with power system dynamic analysis program. The dynamic analysis results (power system post-fault states) are then classified into secure, alert, emergency and system breakdown. The probabilities, minimal cut sets and grid level importance measures (Fussell-Vesely, risk increase and decrease factors) are calculated for the total and partial system breakdown. In this way, the relative importance of the substation devices regarding to the system breakdown can be reached. Also the more and less likely contributing factors to system breakdown are received. With this method, an existing 400 kV transmission grid with its line fault and device failure statistics is analysed. 相似文献
93.
Li H Bochko V Jaaskelainen T Parkkinen J Shen IF 《Journal of the Optical Society of America. A, Optics, image science, and vision》2008,25(11):2805-2816
In this work, we propose a new algorithm for spectral color image segmentation based on the use of a kernel matrix. A cost function for spectral kernel clustering is introduced to measure the correlation between clusters. An efficient multiscale method is presented for accelerating spectral color image segmentation. The multiscale strategy uses the lattice geometry of images to construct an image pyramid whose hierarchy provides a framework for rapidly estimating eigenvectors of normalized kernel matrices. To prevent the boundaries from deteriorating, the image size on the top level of the pyramid is generally required to be around 75 x 75, where the eigenvectors of normalized kernel matrices would be approximately solved by the Nystr?m method. Within this hierarchical structure, the coarse solution is increasingly propagated to finer levels and is refined using subspace iteration. In addition, to make full use of the abundant color information contained in spectral color images, we propose using spectrum extension to incorporate the geometric features of spectra into similarity measures. Experimental results have shown that the proposed method can perform significantly well in spectral color image segmentation as well as speed up the approximation of the eigenvectors of normalized kernel matrices. 相似文献
94.
Heikkinen V Jetsu T Parkkinen J Hauta-Kasari M Jaaskelainen T Lee SD 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(9):2673-2683
For digital cameras, device-dependent pixel values describe the camera's response to the incoming spectrum of light. We convert device-dependent RGB values to device- and illuminant-independent reflectance spectra. Simple regularization methods with widely used polynomial modeling provide an efficient approach for this conversion. We also introduce a more general framework for spectral estimation: regularized least-squares regression in reproducing kernel Hilbert spaces (RKHS). Obtained results show that the regularization framework provides an efficient approach for enhancing the generalization properties of the models. 相似文献
95.
We present a method for controlled connection of gold electrodes with dsDNA molecules (locally on a chip) by utilizing polymerase to elongate single-stranded DNA primers attached to the electrodes. Thiol-modified oligonucleotides are directed and immobilized to nanoscale electrodes by means of dielectrophoretic trapping, and extended in a procedure mimicking PCR, finally forming a complete dsDNA molecule bridging the gap between the electrodes. The technique opens up opportunities for building from the bottom-up, for detection and sensing applications, and also for molecular electronics. 相似文献
96.
Gene‐diet interaction of a common FADS1 variant with marine polyunsaturated fatty acids for fatty acid composition in plasma and erythrocytes among men
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97.
Fasting serum hippuric acid is elevated after bilberry (Vaccinium myrtillus) consumption and associates with improvement of fasting glucose levels and insulin secretion in persons at high risk of developing type 2 diabetes
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98.
Ilkka Somero Jussi Ollila 《工程机械》2014,(12):I0019-I0019
颚式破碎机的破碎腔体积对破碎效率至关重要。与同规格的上一款机型相比,美卓新推出的NordbergC130型颚式破碎机的破碎腔体积增大21%,一次可破碎更多的矿石;其超大的给料口,可确保在恶劣工况下拥有更高产量。 相似文献
99.
Dissolved organic matter (DOM) in 20 surface waters in Eastern Finland were characterized to examine relationships between structural and compositional properties of DOM and partition coefficients (Kp) describing sorption of four model contaminants to DOM and the bioavailability of contaminants by Daphnia magna. The hydrophobic acids (HbA), hydrophobic neutrals (HbN) and hydrophilic (HI) fractions of DOM were separated by XAD-8 resin. The KPs were measured by equilibrium dialysis. Model contaminants were benzo(a)pyrene (BaP), naphthalene (NAPH), 3.3′,4.4′-tetrachlorobiphenyl (TCB) and dehydroabietic acid (DHAA).DOM concentrations varied from 2.0 to 38.3 mg org. C/l in the water series. The percentage of HbA and the aromaticity of DOM, as indicated by the absorptivity at 270 nm (A270) and hydrogen/carbon ratio (H/C ratio), increased with increasing DOM concentration. Significant correlations were observed between KP of BAP, A270 and HbA content of the DOM from different sources. For the other contaminants similar kinds of relationships between Kps and quality parameters of DOM could not be found.The bioavailability of model compounds was decreased by increasing DOM concentration in the water series. For all four model contaminants, measured bioconcentration factors (BCF) correlated well with the A270 of a water and HbA content of the DOM. These results show that the total DOM concentration is an important factor controlling the bioavailability of xenobiotics in natural waters. Besides the quantity also the quality of DOM, like proportion of HbA, can contribute in bioavailability. 相似文献
100.
Vuori Jukka; Silvonen Jussi; Vinokur Amiram D.; Price Richard H. 《Canadian Metallurgical Quarterly》2002,7(1):5
The impact of preventive interventions for the unemployed may vary depending on the context of the labor policies and benefit systems of the country where it is implemented. The Ty?h?n Job Search Program was based on a method developed in the United States for recently unemployed workers. This study examined outcomes of the intervention in the context of the European labor market for participants who had been unemployed for a longer period. A total of 1,261 unemployed Finnish job seekers participated in a randomized field study. At the 6-month follow-up, the program had a beneficial impact on the quality of reemployment, especially among those who had been unemployed for a moderate time period. The program also significantly decreased psychological distress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献