A Victorian Age Proof of the Four Color Theorem

In this paper we have investigated some old issues concerning four color map problem. We have given a general method for constructing counter-examples to Kempe's proof of the four color theorem and then show that all counterexamples can be rule out by re-constructing special 2-colored two paths decomposition in the form of a double-spiral chain of the maximal planar graph. In the second part of the paper we have given an algorithmic proof of the four color theorem which is based only on the coloring faces (regions) of a cubic planar maps. Our algorithmic proof has been given in three steps. The first two steps are the maximal mono-chromatic and then maximal dichromatic coloring of the faces in such a way that the resulting uncolored (white) regions of the incomplete two-colored map induce no odd-cycles so that in the (final) third step four coloring of the map has been obtained almost trivially.Comment: 27 pages, 18 figures, revised versio

Dividend Policy of the ISE Industrial Corporations: The Evidence Revisited (1986-2007)

The study aims to find out whether the disappearing dividends, the decline in the number of dividend payers, the size effect and the increasing dividend/earnings concentration found in several developed and emerging markets exist among the industrials traded in the ISE. The study also analyzes the effects of the reinstatement of mandatory dividend policy in 2003. Using univariate statistical tests, we detect a size effect as well as a high level but stable dividend/ earnings concentration. We find a significant decrease in the number of dividend payers, but we also detect an increasing level of real/nominal dividends driven by the high dividend/ earnings concentration and the increasing level of earnings. The reinstatement of the mandatory dividend policy regulation in 2003 has not been successful in changing the payout policy of industrialsDividends,Payout Policy, Disappearing Dividends, Dividend Types, Mandatory Dividend Policy, Concentration, Size Effect

Are Happier People Better Citizens?

This paper presents evidence on causal influence of happiness on social capital and trust using German Socio-Economic Panel. Exploiting the unexplained cross-sectional variation in individual happiness (residuals) in 1984 to eliminate the endogeneity problem, the paper nds that happier people trust others more, and importantly, help create more social capital. Specifically, they have a higher desire to vote, perform more volunteer work, and more frequently participate in public activities. They also have a higher respect for law and order, hold more association memberships, are more attached to their neighborhood, and extend more help to others. Residual happiness appears to be an indicator of optimism, and has an inverse U-shaped relationship with social capital measures. The findings also suggest that the relationship between happiness and social capital strengthened in the world in the last decade.happiness, trust, social capital, optimism.

Analysis of small-scale rotor hover performance data

Rotor hover-performance data from a 1/6-scale helicopter rotor are analyzed and the data sets compared for the effects of ambient wind, test stand configuration, differing test facilities, and scaling. The data are also compared to full scale hover data. The data exhibited high scatter, not entirely due to ambient wind conditions. Effects of download on the test stand proved to be the most significant influence on the measured data. Small-scale data correlated resonably well with full scale data; the correlation did not improve with Reynolds number corrections

Reversing the Question: Does Happiness Affect Consumption and Savings Behavior?

I examine the impact of happiness on consumption and savings behavior using data from the DNB Household Survey from the Netherlands and the German Socio-Economic Panel. Instrumenting individual happiness with regional sunshine, the results suggest that happier people save more, spend less, and have a lower marginal propensity to consume. Happier people take more time for making decisions and have more control over expenditures; they expect a longer life and (accordingly) seem more concerned about the future than the present; they also expect less inflation in the future.happiness, savings, consumption, weather

Effect of organoclay on the physical properties of UV-curable coatings

The combination of UV-curing and nanocomposite technology has been studied to produce cost-effective coatings with superior physical and mechanical properties. The clay was modified with dimethyl dihydrogenated-tallow quaternary ammonium salt and made organophilic. The effect of the organoclay(2-10 phr) on curing rate, mechanical, thermal and physical properties of a urethane-acrylate coating has been determined. X-ray diffraction analysis, AFM, SEM and TEM images as well as the tensile properties of different formulations have confirmed the uniform distribution of organoclay in polymer matrix. At 3 phr organoclay addition, the UV-cured film exhibited the best mechanical performance due to the formation of both intercalated and exfoliated morphologies. Curing time was reduced and the initial thermal decomposition temperature shifted 50°C to higher temperature by the incorporation of small amount of organoclay. The nanocomposite coating was also found to be more resistant against scratching compared with clay-free coating

Why Is The World Getting Older? The Influence of Happiness on Mortality

World life expectancy has risen by around 20 years in the last 50 years. This period has also witnessed rising happiness levels around the world suggesting that happiness might be one of the causes behind the decline in mortality. We investigate the relationship between happiness and mortality using the German Socio-Economic Panel. We consider doctor visits, self-reported health, and presence of chronic illness as health measures. After controlling for initial health conditions, we find that happiness extends life expectancy. 10 percent increase in happiness decreases probability of death by four percent, and this effect is more pronounced for men and younger people. Happiness plays a more important role for chronically ill people in decreasing mortality than for those who are not chronically ill. The positive influence of happiness on mortality can offset the negative impact of chronic illness. Marriage decreases mortality and this effect appears to work through increased happiness.happiness; mortality; health; chronic illness.

Why Is the World Getting Older?: The Influence of Happiness on Mortality

World life expectancy has risen by around 20 years in the last 50 years. This period has also witnessed rising happiness levels around the world suggesting that happiness might be one of the causes behind the decline in mortality. We investigate the relationship between happiness and mortality using the German Socio-Economic Panel. We consider doctor visits, self-reported health, and presence of chronic illness as health measures. After controlling for initial health conditions, we find that happiness extends life expectancy. 10 percent increase in happiness decreases probability of death by four percent, and this effect is more pronounced for men and younger people. Happiness plays a more important role for chronically ill people in decreasing mortality than for those who are not chronically ill. The positive influence of happiness on mortality can offset the negative impact of chronic illness. Marriage decreases mortality and this effect appears to work through increased happiness.Happiness, mortality, health, chronic illness