• Title/Summary/Keyword: theory of natural energy

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Kinetic Energy Release in the Fragmentation of tert-Butylbenzene Molecular Ions. A Mass-analyzed Ion Kinetic Energy Spectrometric (MIKES) Study

  • Choe, Joong-Chul;Kim, Byung-Joo;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
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    • v.10 no.2
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    • pp.167-171
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    • 1989
  • Kinetic energy release in the fragmentation of tert-butylbenzene molecular ion was investigated using mass-analyzed ion kinetic energy spectrometry. Method to estimate kinetic energy release distribution (KERD) from experimental peak shape has been explained. Experimental KERD was in good agreement with the calculated result using phase space theory. Effect of dynamical constraint was found to be important.

A Study on Analysis of Eco-space from a Standpoint of Poong-soo -On the Ground of Korean Traditional Poong-soo- (풍수지리관점(風水地理觀點)에서 본 생태공간해석(生態空間解析)에 관한 연구(硏究) -한국(韓國)의 전통적(傳統的) 풍수지리(風水地理)를 중심(中心)으로-)

  • Hyun, Young Jo;Lee, Dong Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.6
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    • pp.49-63
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    • 2002
  • While the existing feng-shui is largely approached architecturally and geographically as positive place and negative place, the study is characterized by approaching and analyzing poong-soo environmentally. The theory of Eco-city as one of modern-city theories is worthy of studying by analyzing the merits and demerits of it and combining it with poong-soo and making a new alternative theory. Theory of Natural Energy and principle of Natural Balance. Thus, poong-soo ideas can be an important view of nature in analyzing the theory of Eco-city which is coming to the front these days. In particular, we try to make use of poong-soo as a basic theory for a city planning and design by studying and analyzing and combining the merits and demerits of Eco-city with poong-soo and presenting a new alternative method of a stable and balanced "refined city development". On the other hand, we connect 'theory with practice(or experience)' by covering all spaces variably from minimum unit space to city-space from the standpoint of poong-soo. But, problem of the Theory of Eco-city from the view of poong-soo are too artificial and theoretical, even if ideal. Conversely, from the view of Eco-city, the possibility of the practicability of Korean poong-soo is judged to be high. we can tell that among capital cities applied by poong-soo, historical cities like Beijing in China, Seoul in Korea and Tokyo in Japan are poong-soo cities in accordance with the requirements of Eco-city.

Theoretical Studies on 2-Hexylthieno[3,2-b]thiophene End-Capped Oligomers for Organic Semiconductor Materials

  • Park, Young-Hee;Kim, Yun-Hi;Kwon, Soon-Ki;Koo, In-Sun;Yang, Ki-Yull
    • Bulletin of the Korean Chemical Society
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    • v.33 no.4
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    • pp.1213-1219
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    • 2012
  • The reorganization energy and the spectroscopic properties of 2,6-bis(5'-hexyl-thieno[3,2-b]thiophene-2'- yl)naphthalene (DH-TNT) and 2,6-bis(5'-hexyl-thieno[3,2-b]thiophene-2'-yl)anthracene (DH-TAT), which are composed of an acene unit and alkylated thienothiophene on both sides, as organic materials for display devices were calculated and the results were compared with experimental values. The lower reorganization energy of the DH-TAT over the DH-TNT calculated by the density functional theory is attributed to a smaller vibrational distortion because of the heavier building block of DH-TAT, and it shows a good field effect performance over the DH-TNT. The calculated spectra and the other spectroscopic characteristic of the compounds are well consistent with those of observed results.

Vibration analysis of generalized thermoelastic microbeams resting on visco-Pasternak's foundations

  • Zenkour, Ashraf M.
    • Advances in aircraft and spacecraft science
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    • v.4 no.3
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    • pp.269-280
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    • 2017
  • The natural vibration analysis of microbeams resting on visco-Pasternak's foundation is presented. The thermoelasticity theory of Green and Naghdi without energy dissipation as well as the classical Euler-Bernoulli's beam theory is used for description of natural frequencies of the microbeam. The generalized thermoelasticity model is used to obtain the free vibration frequencies due to the coupling equations of a simply-supported microbeam resting on the three-parameter viscoelastic foundation. The fundamental frequencies are evaluated in terms of length-to-thickness ratio, width-to-thickness ratio and three foundation parameters. Sample natural frequencies are tabulated and plotted for sensing the effect of all used parameters and to investigate the visco-Pasternak's parameters for future comparisons.

Adaptive Data Association for Multi-Target Tracking using Relaxation

  • Lee, Yang-Weon;Hong Jeong
    • Journal of Electrical Engineering and information Science
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    • v.3 no.2
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    • pp.267-273
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    • 1998
  • This paper introduces an adaptive algorithm determining the measurement-track association problem in multi-target tracking(MTT). We model the target and measurement relationships with mean field theory and then define a MAP estimate for the optimal association. Based on this model, we introduce an energy function defined over the measurement space, that incorporates the natural constraints for target tracking. To find the minimizer of the energy function, we derived a new adaptive algorithm by introducing the Lagrange multipliers and local dual theory. Through the experiments, we show that this algorithm is stable and works well in general environments. Also the advantages of the new algorithm over other algorithms are discussed.

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The Potential Energy Surface of BH5 and the Rate of the Hydrogen Scrambling

  • Kim, Kyung-Hyun;Kim, Yong-Ho
    • Bulletin of the Korean Chemical Society
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    • v.24 no.6
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    • pp.763-770
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    • 2003
  • The $BH_5$ molecule, which is suggested as an intermediate of the acidolysis of $BH_4^-$, contains a weak two-electron-three-center bond and it requires extremely high-level of theories to calculate the energy and structure correctly. The structures and energies of $BH_5$ and the transition state for the hydrogen scrambling have been studied using recently developed multi-coefficient correlated quantum mechanical methods (MCCMs). The dissociation energies and the barrier heights agree very well with the previous results at the CCSD(T)/ TZ(3d1f1g, 2p1d) level. We have also calculated the potential energy curves for the dissociation of $BH_5$ to $BH_3$ and $H_2$. The lower levels of theory were unable to plot correct potential curves, whereas the MCCM methods give very good potential energy curves and requires much less computing resources than the CCSD(T)/ TZ(3d1f1g,2p1d) level. The potential energy of the $BH_5$ scrambling has been obtained by the multiconfiguration molecular mechanics algorithm (MCMM), and the rates are calculated using the variational transition state theory including multidimensional tunneling approximation. The rate constant at 300 K is 2.1 × $10^9s^{-1}$, and tunneling is very important.

A Study on Natural Gas Cooperation in North East Asia from the Viewpoint of Economic Integration Theory (동북아 천연가스 사업의 협력 가능성 분석 : 경제통합론을 중심으로)

  • Jin, Sang-Hyeon;Heo, Seong-Yeop
    • Journal of the Korean Institute of Gas
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    • v.23 no.1
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    • pp.1-11
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    • 2019
  • The Korean government has tried to introduce pipeline natural gas from Russia, instead of liquefied natural gas from Middle East Asia since 1990s. While this energy cooperation in North East Asia has been discussed in real politics and academic societies, the previous studies have shown the limits on policy implication because they just suggest necessity and possess the problems of weak theoretical frameworks. Therefore, this study tries to analyze the motivations, conditions, and stages for energy cooperation in this region from the viewpoint of economic integration theory. As a result of analysis, these countries in North East Asia have only one motivation, namely economic interest. On the contrary, they have several conditions including real benefit, complementation in economic structures, and convergence in policy goals. In conclusion, this study suggests that low level cooperation such as preferential trade agreement in the field of natural gas is possible and necessary in North East Asia.

Vibration analysis of porous nanocomposite viscoelastic plate reinforced by FG-SWCNTs based on a nonlocal strain gradient theory

  • Khazaei, Pegah;Mohammadimehr, Mehdi
    • Computers and Concrete
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    • v.26 no.1
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    • pp.31-52
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    • 2020
  • This paper investigates the size dependent effect on the vibration analysis of a porous nanocomposite viscoelastic plate reinforced by functionally graded-single walled carbon nanotubes (FG-SWCNTs) by considering nonlocal strain gradient theory. Therefore, using energy method and Hamilton's principle, the equations of motion are derived. In this article, the effects of nonlocal parameter, aspect ratio, strain gradient parameter, volume fraction of carbon nanotubes (CNTs), damping coefficient, porosity coefficient, and temperature change on the natural frequency are perused. The innovation of this paper is to compare the effectiveness of each mentioned parameters individually on the free vibrations of this plate and to represent the appropriate value for each parameter to achieve an ideal nanocomposite plate that minimizes vibration. The results are verified with those referenced in the paper. The results illustrate that the effect of damping coefficient on the increase of natural frequency is significantly higher than the other parameters effect, and the effects of the strain gradient parameter and nonlocal parameter on the natural frequency increase are less than damping coefficient effect, respectively. Furthermore, the results indicate that the natural frequency decreases with a rise in the nonlocal parameter, aspect ratio and temperature change. Also, the natural frequency increases with a rise in the strain gradient parameter and CNTs volume fraction. This study can be used for optimizing the industrial and medical designs, such as automotive industry, aerospace engineering and water purification system, by considering ideal properties for the nanocomposite plate.

A study on the magnetic flux distribution of 3-phase 4-pole induction motor by finite element method (유한요소법에 의한 삼상유도전동기의 자속분포해석에 관한 연구)

  • 임달호;현동석;임태빈
    • 전기의세계
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    • v.30 no.4
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    • pp.219-226
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    • 1981
  • The magnetic field distribution in saturable iron part of electromagnetic energy conversion divices is defined by the nonlinear quasi-Poisson enquation that is described the electromagnetic field characteristics and satisfied the natural boundary condition. The solution of this equation is obtained by minimizing an energy functional by means of trial function that defined in triangular subregion of two-dimensional field region. As a result, the accuracy of the machine design is increased by use of its solution. In this respect, this study is developed the basic theory to analyze the magnetic flux distribution in saturable iron part and air gap of induction motor that its secondary part is short circuit by the variational principle, the minimized theory of energy functional, the application of F.E.M., and treatment of computer. As theoritical data compared with the practics, the validity of the theory in this study is supported by experimental findings.

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Buckling analysis of FGM Euler-Bernoulli nano-beams with 3D-varying properties based on consistent couple-stress theory

  • Hadi, Amin;Nejad, Mohammad Zamani;Rastgoo, Abbas;Hosseini, Mohammad
    • Steel and Composite Structures
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    • v.26 no.6
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    • pp.663-672
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    • 2018
  • This paper contains a consistent couple-stress theory to capture size effects in Euler-Bernoulli nano-beams made of three-directional functionally graded materials (TDFGMs). These models can degenerate into the classical models if the material length scale parameter is taken to be zero. In this theory, the couple-stress tensor is skew-symmetric and energy conjugate to the skew-symmetric part of the rotation gradients as the curvature tensor. The material properties except Poisson's ratio are assumed to be graded in all three axial, thickness and width directions, which it can vary according to an arbitrary function. The governing equations are obtained using the concept of minimum potential energy. Generalized differential quadrature method (GDQM) is used to solve the governing equations for various boundary conditions to obtain the natural frequencies of TDFG nano-beam. At the end, some numerical results are performed to investigate some effective parameter on buckling load. In this theory the couple-stress tensor is skew-symmetric and energy conjugate to the skew-symmetric part of the rotation gradients as the curvature tensor.