• Title/Summary/Keyword: Many-body interaction

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Theoretical Study of Positronium Atoms Using Frozen Gaussian-type Geminals

  • Takatsuka, Akio;Ten no, Seiichiro
    • Bulletin of the Korean Chemical Society
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    • 제24권6호
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    • pp.859-863
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    • 2003
  • We report on the theoretical positron affinities of closed-shell atomic anions. The second-order many-body perturbation theory is applied taking the positron-electron interaction as a perturbation. The corrections for the complete basis set effects to the second order affinity are calculated based on the variational and nonvariational energy functionals of explicitly correlated geminals. It is shown that the explicitly correlated methods accelerate the convergence of the expansion significantly giving the account of the cusp behavior outside the orbital space.

Ab initio Study on Structures, Energies and Vibrations of Methylammonium-(water)$_n$ (n=1-3) Complexes

  • 김광연;조융인;부두완
    • Bulletin of the Korean Chemical Society
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    • 제22권6호
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    • pp.597-604
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    • 2001
  • The reaction of [(2-N,N-dimethylaminomethyl) pheny] methylvinychlorosiane with t-BuLi in hexane solvent gave dimers, five isomeric 1,3-disilacyslobutanes which were weparated and charaterized. In trapping experiments with various trapping agents, no corresponding silene-trapping aduct was observed. We suggest that more important species for the formation of five isomeric dimers might be the zwitterionic species generated by virtue of intramolecular donor atom rather than the silene.

서양 역사복식에 나타난 과장적 헤어스타일의 미적 특성 연구 (A Study on the Aesthetic Characteristics of Exaggerated Hairstyle in the Western Costume)

  • 이연희;성광숙
    • 복식
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    • 제65권8호
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    • pp.110-124
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    • 2015
  • This study examined a phenomenon of exaggerated hairstyle in the history of Western custom through publications related with Western costume and research papers. By adopting the criteria of Delong, M. R. to analyze visual forms shown by interaction between human body and costume worn over the body, it analyzed the formative characteristics by the interaction between hairstyle and costume. In addition, it inferred the aesthetic characteristics through content analysis of examined phenomenon focusing on socio-cultural background and costume socio-psychological precedent studies. Formative characteristics of exaggerated hairstyle applied by analysis criteria of Delong, M. R. were in pursuit of the emphasis style. This was clearly and intensively recognized by forming spaces for mostly closure style, part style, three dimensional style, determinate style, and space separation style. Regarding the interaction between hair and ornamentations, 'precedence of ornamentation' was pursued as ornamentations were recognized earlier than the hair itself. It means associative meanings of the surface effect were accompanied by emotions of 'intensiveness' and the pursuit of the attractive style. As for the interaction between hairstyle and costume, there were many cases of pursuing 'continuity' mutually and visually by connecting the hairstyle and the costume. Aesthetic characteristics of exaggerated hairstyle were inferred as 1) the expression of the sprite of the age(i.e. art, culture, politics, society, ideology, religion), 2) symbols of wealth, class, authority, and excellence, 3) pursuit of addicted desire to ornament, and 4) harmony through continuity with costume. This study verified that hairstyle was connected as a part of costume, or formed as a way to express deeper human psychology beyond just a part of a costume. It was also confirmed that hairstyle was an expressive method to express the spirit of the age, such as art, culture, society, religion, ideology.

Vehicle/track dynamic interaction considering developed railway substructure models

  • Mosayebi, Seyed-Ali;Zakeri, Jabbar-Ali;Esmaeili, Morteza
    • Structural Engineering and Mechanics
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    • 제61권6호
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    • pp.775-784
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    • 2017
  • This study is devoted to developing many new substructure models for ballasted railway track by using the pyramid model philosophy. As the effect of railway embankment has been less considered in the previous studies in the field of vehicle/track interaction, so the present study develops the pyramid models in the presence of railway embankment and implements them in vehicle/track interaction dynamic analyses. Considering a moving car body as multi bodies with 10 degrees of freedom and the ballasted track including rail, sleeper, ballast, subgrade and embankment, two categories of numerical analyses are performed by considering the new substructure systems including type A (initiation of stress overlap areas in adjacent sleepers from the ballast layer) or type B (initiation of stress overlap areas in adjacent sleepers from the subgrade layer). A comprehensive sensitivity analyses are performed on effective parameters such as ballast height, sleepers spacing and sleeper width. The results indicate that the stiffness of subgrade, embankment and foundation increased by increasing the ballast height. Also, by increasing the ballast height, rail and ballast vertical displacement decreased.

Robust 2D human upper-body pose estimation with fully convolutional network

  • Lee, Seunghee;Koo, Jungmo;Kim, Jinki;Myung, Hyun
    • Advances in robotics research
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    • 제2권2호
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    • pp.129-140
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    • 2018
  • With the increasing demand for the development of human pose estimation, such as human-computer interaction and human activity recognition, there have been numerous approaches to detect the 2D poses of people in images more efficiently. Despite many years of human pose estimation research, the estimation of human poses with images remains difficult to produce satisfactory results. In this study, we propose a robust 2D human body pose estimation method using an RGB camera sensor. Our pose estimation method is efficient and cost-effective since the use of RGB camera sensor is economically beneficial compared to more commonly used high-priced sensors. For the estimation of upper-body joint positions, semantic segmentation with a fully convolutional network was exploited. From acquired RGB images, joint heatmaps accurately estimate the coordinates of the location of each joint. The network architecture was designed to learn and detect the locations of joints via the sequential prediction processing method. Our proposed method was tested and validated for efficient estimation of the human upper-body pose. The obtained results reveal the potential of a simple RGB camera sensor for human pose estimation applications.

Network Graph Analysis of Gene-Gene Interactions in Genome-Wide Association Study Data

  • Lee, Sungyoung;Kwon, Min-Seok;Park, Taesung
    • Genomics & Informatics
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    • 제10권4호
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    • pp.256-262
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    • 2012
  • Most common complex traits, such as obesity, hypertension, diabetes, and cancers, are known to be associated with multiple genes, environmental factors, and their epistasis. Recently, the development of advanced genotyping technologies has allowed us to perform genome-wide association studies (GWASs). For detecting the effects of multiple genes on complex traits, many approaches have been proposed for GWASs. Multifactor dimensionality reduction (MDR) is one of the powerful and efficient methods for detecting high-order gene-gene ($G{\times}G$) interactions. However, the biological interpretation of $G{\times}G$ interactions identified by MDR analysis is not easy. In order to aid the interpretation of MDR results, we propose a network graph analysis to elucidate the meaning of identified $G{\times}G$ interactions. The proposed network graph analysis consists of three steps. The first step is for performing $G{\times}G$ interaction analysis using MDR analysis. The second step is to draw the network graph using the MDR result. The third step is to provide biological evidence of the identified $G{\times}G$ interaction using external biological databases. The proposed method was applied to Korean Association Resource (KARE) data, containing 8838 individuals with 327,632 single-nucleotide polymorphisms, in order to perform $G{\times}G$ interaction analysis of body mass index (BMI). Our network graph analysis successfully showed that many identified $G{\times}G$ interactions have known biological evidence related to BMI. We expect that our network graph analysis will be helpful to interpret the biological meaning of $G{\times}G$ interactions.

Heat resistance of carbon nanoonions by molecular dynamics simulation

  • Wang, Xianqiao;Lee, James D.
    • Interaction and multiscale mechanics
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    • 제4권4호
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    • pp.247-255
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    • 2011
  • Understanding the structural stability of carbon nanostructure under heat treatment is critical for tailoring the thermal properties of carbon-based material at small length scales. We investigate the heat resistance of the single carbon nanoball ($C_{60}$) and carbon nanoonions ($C_{20}@C_{80}$, $C_{20}@C_{80}@C_{180}$, $C_{20}@C_{80}@C_{180}C_{320}$) by performing molecular dynamics simulations. An empirical many-body potential function, Tersoff potential, for carbon is employed to calculate the interaction force among carbon atoms. Simulation results shows that carbon nanoonions are less resistive against heat treatment than single carbon nanoballs. Single carbon nanoballs such $C_{60}$ can resist heat treatment up to 5600 K, however, carbon nanoonions break down after 5100 K. This intriguing result offers insights into understanding the thermal-mechanical coupling phenomena of nanodevices and the complex process of fullerenes' formation.

항우울제와 연관약물의 약물상호작용 (Antidepressants and Related Drug Interactions)

  • 이민수
    • 생물정신의학
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    • 제7권1호
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    • pp.21-33
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    • 2000
  • As the clinical practice of using more than one drug at a time increase, the clinician is faced with ever-increasing number of potential drug interactions. Although many interactions have little clinical significances, some may interfere with treatment or even be life-threatening. This review provides a better understanding of drug-drug interactions often encountered in pharmacotherapy of depression. Drug interactions can be grouped into two principal subdivisions : pharmacokinetic and pharmacodynamic. These subgroups serve to focus attention on possible sites of interaction as a drug moves from the site of administration and absorption to its site of action. Pharmacokinetic processes are those that include transport to and from the receptor site and consist of absorption, distribution on body tissue, plasma protein binding, metabolism, and excretion. Pharmacodynamic interactions occur at biologically active sites. In this review, emphasis is placed on antidepressant medications, how they are metabolized by the P450 system, and how they alter the metabolism of other drugs. When prescribing antidepressant medications, the clinician must consider the drug-drug interactions that are potentially problematic.

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What Is Integrative Medicine?

  • Jung, Seungpil
    • Journal of Yeungnam Medical Science
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    • 제30권2호
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    • pp.79-82
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    • 2013
  • The demand for complementary and alternative medicine (CAM) is increasing worldwide. High-technology medicine is not always effective and is often accompanied by neglected self-care and high cost. Also, conventional medicine has become dependent on expensive technological solutions to health problems. Integrated medicine is not simply a synonym for complementary medicine. It involves the understanding of the interaction of the mind, body, and spirit and how to interpret this relationship in the dynamics of health and disease. Integrative medicine shifts the orientation of the medical practice from a disease-based approach to a healing-based approach. In South Korea, CAM education was first provided 20 years ago, and integrative medicine is becoming part of the current mainstream medicine. Increasing numbers of fellowships in integrative medicine are being offered in many academic health centers in the U.S. Also, it has emerged as a potential solution to the American healthcare crisis and chronic diseases, which are bankrupting the economy. It provides care that is patient-centered, healing-oriented, emphasizes the therapeutic relationship, and uses therapeutic approaches originating from conventional and alternative medicine.

차량동역학 해석 프로그램 AutoDyn7의 동력전달장치 모델 (Development of Powertrain Model for Vehicle Dynamic Analysis Program, AutoDyn7)

  • 손정현;유완석;김두현
    • 한국자동차공학회논문집
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    • 제9권2호
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    • pp.185-191
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    • 2001
  • In many papers, the powertrain system generally has been madeled as one-dimensional torque model. One-dimensional powertrain model may calculate the torque correctly but it does not consider the non-rotational degrees-of-freedom of the powertrain components and the interaction of these degrees-of-freedom with the vehicle body frame and suspension. To consider the non-rotational degrees of freedom, the differential is modeled as a three-dimensional rigid body in this paper. A constant velocity joint is newly formulated and a relative constraint is also formulated to model the motion transfer due to gear ratio of the differential. Implementing the proposed powertrain system in the multibody model, more detail dynamic responses can be obtained. Obtained outputs such as reaction torques on the constant velocity joint and reaction forces on the rack can be useful data in the design of a powertrain.

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