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Electron Spin and Proton Spin in the Hydrogen and Hydrogen-Like Atomic Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52202#.VIj7tMnQrzE Author(s) Stanisław Olszewski * Affiliation(s) Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland . ABSTRACT The mechanical angular momentum and magnetic moment of the electron and proton spin have been calculated semiclassically with the aid of the uncertainty principle for energy and time. The spin effects of both kinds of the elementary particles can be expressed in terms of similar formulae. The quantization of the spin motion has been done on the basis of the old quantum theory. It gives a quantum number n = 1/2 as the index of the spin state acceptable for both the electron and proton ...
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Remarks on the Complexity of Signed k-Domination on Graphs

Read  full  paper  at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=53574#.VMnXsCzQrzE Author(s)    Chuan-Min Lee 1 , Cheng-Chien Lo 1 , Rui-Xin Ye 2 , Xun Xu 2 , Xiao-Han Shi 2 , Jia-Ying Li 2 Affiliation(s) 1 Department of Computer and Communication Engineering, Ming Chuan University, The First American University in Asia, Taoyuan, Taiwan, Chinese Taipei . 2 Department of Electronic Information Engineering, Fuzhou University, Fuzhou, China . ABSTRACT This paper is motivated by the concept of the signed k-domination problem and dedicated to the complexity of the problem on graphs. For any fixed nonnegative integer k, we show that the signed k-domination problem is NP-complete for doubly chordal graphs. For strongly chordal graphs and distance-hereditary graphs, we show that the signed k-domination problem can be solved in polynomial time. We also show that the problem is linear-time solvable for trees, interval graphs, and chord...
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A Review of Technical Requirements for High Penetration of Wind Power Systems

Read full paper at: http://www.scirp.org/journal/PaperInformation.aspx?PaperID=52361#.VJN8VcCAM4 Author(s)    Yuan-Kang Wu 1 , Tung-Ching Lee 2 , Ting-Yen Hsieh 2 , Wei-Min Lin 2 Affiliation(s) 1 Department of Electrical Engineering, National Chung-Cheng University, Chiayi, Taiwan . 2 Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan . ABSTRACT Renewable portfolio targets have been established in many regions around the world. Regional targets such as 20% renewable energy by year 2020 are not uncommon. As the levels of wind power penetration increase, there are many power system impacts. This work investigated possible challenges and technic...
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