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Search Results: 1 - 10 of 463080 matches for " S. G. "
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Ground State of 4-7H Considering Internal Collective Rotation  [PDF]
S. Paschalis, G. S. Anagnostatos
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.45B012
Abstract:

The g.s. of heavy and superheavy hydrogen isotopes, namely 4-7 H, are successfully examined by applying the Isomorphic Shell Model. Properties examined are binding energies and effective radii. The novelty of the present work is that, due to the small number of nucleons involved and the subsequently large deformation, an internal collective rotation appears which is inseparable from the usual internal motion even in the ground states of these nuclei, i.e., for such nuclei the adiabatic approximation is not valid. This extra degree of freedom leads to a reduction of binding energies, an increase of effective radii, and an increase of level widths.

Reliability Optimization of Entropy Based Series-Parallel System Using Global Criterion Method  [PDF]
G. S. MAHAPATRA
Intelligent Information Management (IIM) , 2009, DOI: 10.4236/iim.2009.13021
Abstract: In this paper, we have considered a series-parallel system to find out optimum system reliability with an additional entropy objective function. Maximum system reliability of series-parallel system is depending on proper allocation of redundancy component in different stage. The goal of entropy based reliability redundancy allocation problem is to find optimal number of redundancy component in each stage such a manner that maximize the system reliability subject to available total system cost. Global criterion method is used to analyze entropy based reliability optimization problem with different weight function of objective functions. Numerical examples have been provided to illustrate the model.
Quantum Isomorphic Shell Model: Multi-Harmonic Shell Clustering of Nuclei  [PDF]
G. S. Anagnostatos
Journal of Modern Physics (JMP) , 2013, DOI: 10.4236/jmp.2013.45B011
Abstract: The present multi-harmonic shell clustering of a nucleus is a direct consequence of the fermionic nature of nucleons and their average sizes. The most probable form and the average size for each proton or neutron shell are here presented by a specific equilibrium polyhedron of definite size. All such polyhedral shells are closely packed leading to a shell clustering of a nucleus. A harmonic oscillator potential is employed for each shell. All magic and semi-magic numbers, g.s. single particle and total binding energies, proton, neutron and mass radii of 40Ca, 48Ca, 54Fe, 90Zr, 108Sn, 114Te, 142Nd, and 208Pb are very successfully predicted.

 

Polyhedral symmetry and quantum mechanics  [PDF]
G. S. Anagnostatos
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.64024
Abstract:

A thorough study of regular and quasi-regular polyhedra shows that the symmetries of these polyhedra identically describe the quantization of orbital angular momentum, of spin, and of total angular momentum, a fact which permits one to assign quantum states at the vertices of these polyhedra assumed as the average particle positions. Furthermore, if the particles are fermions, their wave function is anti-symmetric and its maxima are identically the same as those of repulsive particles, e.g., on a sphere like the spherical shape of closed shells, which implies equilibrium of these particles having average positions at the aforementioned maxima. Such equilibria on a sphere are solely satisfied at the vertices of regular and quasi-regular polyhedra which can be associated with the most probable forms of shells both in Nuclear Physics and in Atomic Cluster Physics when the constituent atoms possess half integer spins. If the average sizes of the constituent particles are known, then the average sizes of the resulting shells become known as well. This association of Symmetry with Quantum Mechanics leads to many applications and excellent results.

Teacher Candidates’ (Pedagogical Formation Students’) Communication Skills  [PDF]
Süleyman G?ksoy
Creative Education (CE) , 2014, DOI: 10.4236/ce.2014.514152
Abstract:

The purpose of this study is to identify pedagogical formation students’ (teacher candidates’) communication skills based on their perceptions. The study sought answers to the following research question: What are the perceptions of pedagogical formation students (teacher candidates) related to their communication skills? Assessment of pedagogical formation students’ (teacher candidates’) perceptions regarding their communication skills was undertaken through qualitative research methods. Qualitative data collected with the help of semi-structured interview form were analyzed in terms of content. The study was conducted with the participation of 48 teacher candidates attending pedagogical formation classes at Düzce University during 2013-2014 academic year. According to the data obtained at the end of the study, teacher candidates are aware of the necessity and importance of communication. They are aware that the prerequisite for being contented, successful and social individuals and professionals is healthy and good communication with others. Teacher candidates know the importance and necessity of body language in effective communication and generally prefer to use it. They are also aware of the need for written and oral communication when required. Psychological situations such as anxiety, stress, lack of self-efficacy, timidity, fear and excitement are regarded as barriers that inhibit communication. These barriers are followed by being misunderstood, lack of feedback and language, culture, prior information and prejudices related to inappropriate context/environment and persons involved in communication. Teacher candidates express that they can develop communication skills by participating in social activities. They also state that they can develop communication skills by reading books/articles/research findings, participating in courses/seminars/conferences, meeting new and different people and taking training-expert support.

Air-Water Cooling System for Switch-Mode Power Supplies  [PDF]
G. Casano, S. Piva
Journal of Electronics Cooling and Thermal Control (JECTC) , 2015, DOI: 10.4236/jectc.2015.53005
Abstract: The results are presented of an experimental investigation of heat transfer in an air-liquid cooling system for a Switch-Mode Power Supply (SMPS) for TV digital power amplifiers. Since these SMPSs are characterized by high power and high compactness, thereby making the standard cooling techniques difficult to be used, a new cooling system is developed, using water and air as the cooling media. The active components (MOSFETs) are cooled with a liquid cold-plate, the passive ones (condensers, transformers, coils) with an air flow, in turn cooled by the cold-plate. By inserting the cooling system in an experimental tool where it is possible to control the cooling water, measurements are made of temperature in the significant points of the SMPS. The electric efficiency is also measured. The evaluation of the thermal performance of this cooling system is useful in order to limit its maximum operational temperature. The efficacy of the cooling system is demonstrated; the trends of efficiency and power dissipation are evidenced.
The Effect of Mass Ratio and Air Damper Characteristics on the Resonant Response of an Air Damped Dynamic Vibration Absorber  [PDF]
R. G. Todkar, S. G. Joshi
Modern Mechanical Engineering (MME) , 2011, DOI: 10.4236/mme.2011.12012
Abstract: In this paper, it is shown that, a road vehicle 2DOF air damped quartercar suspension system can conveniently be transformed into a 2DOF air damped vibrating system representing an air damped dynamic vibration absorber (DVA) with an appropriate change in the ratio µ of the main mass and the absorber mass i.e. when mass ratio µ >> 1. Also the effect of variation of the mass ratio, air damping ratio and air spring rate ratio, on the motion transmissibility at the resonant frequency of the main mass of the DVA has been dis- cussed. It is shown that, as the air damping ratio in the absorber system increases, there is a substantial decrease in the motion transmissibility of the main mass system where the air damper has been modeled as a Maxwell type. Optimal value of the air damping ratio for the minimum motion transmissibility of the main mass of the system has been determined. An experimental setup has been designed and developed with a control system to vary air pressure in the damper in the absorber system. The motion transmissibility characteristics of the main mass system have been obtained, and the optimal value of the air damping ratio has been determined for minimum motion transmissibility of the main mass of the system
Ecophysiological response to irrigation of two olive cultivars grown in a high-density orchard  [PDF]
G. A. Vivaldi, G. Strippoli, S. Camposeo
Agricultural Sciences (AS) , 2013, DOI: 10.4236/as.2013.48A003
Abstract:

High-density oliveculture system needs irrigation and introduces new cultivars in new environments. So the evaluation of varietal ecophysiological response to irrigation is a crucial topic. For this reason it was planned a research on two cultivars, Coratina and Arbequina, trained according to high-density system. In 2009 the irrigation was conducted according to the conventional management by applying an irrigation frequency of 4 days. The leaf water potentials reached values similar to the limits reported for the recovery within 48 hours. However, plants showed a leaf water status and gas exchange recovery just after 24 hours from watering. The results highlighted some varietal differences: Arbequina showed a better response to irrigation, while Coratina performed a higher water use efficiency by a lower leaf transpiration.

Advancing the Backtrack Optimization Technique to Obtain Forecasts of Potential Crisis Periods  [PDF]
E. G. Lisgara, G. I. Karolidis, G. S. Androulakis
Applied Mathematics (AM) , 2012, DOI: 10.4236/am.2012.330214
Abstract: Financial crisis is an unfortunate reality that overshadows any financial system regardless its profitability and the level it functions. The appearance of crises across financial markets, especially during the 1990s that the internationalized markets adopted a rather approachable character, imposed severe costs in financial and social systems. With this paper is proposed the generation of a future interval of time that is vulnerable to enclose the burst of a financial crisis. A time series consisted of approximations of the local Lipschitz constant is examined and in the proposed forecasting approach this constant holds the crisis indicator role. Further the application of two different optimization techniques over the Lipschitz-made time series results to the generation of a future period of time; this interval is likely to envelop the burst of a forthcoming crisis. The usage of a future interval of time empowers the predicting ability of the methodology by providing warning signs priory to the actual crisis burst. To this direction, the obtained results offer strong evidence that the method may be characterized as an Early Warning System (EWS) for financial crisis prediction.
Effect of Processing Paramters on Metal Matrix Composites: Stir Casting Process  [PDF]
G. G. Sozhamannan, S. Balasivanandha Prabu, V. S. K. Venkatagalapathy
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2012, DOI: 10.4236/jsemat.2012.21002
Abstract: Conventional stir casting process has been employed for producing discontinuous particle reinforced metal matrix composites for decades. The major problem of this process is to obtain sufficient wetting of particle by liquid metal and to get a homogenous dispersion of the ceramic particles. In the present study, aluminium metal matrix composites were fabricated by different processing temperatures with different holding time to understand the influence of process parameters on the distribution of particle in the matrix and the resultant mechanical properties. The distribution is examined by microstructure analysis, hardness distribution and density distribution.
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