• 제목/요약/키워드: string theory

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RECENT PROGRESS IN STRING INFLATIONARY COSMOLOGY

  • REY Soo-JONG
    • 천문학회지
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    • 제29권spc1호
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    • pp.11-14
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    • 1996
  • Super-inflation driven by dilaton/moduli kinetic energy is naturally realized in compactified string theory. Discussed are selected topics of recent development in string inflationary cosmology: kinematics of super-inflation, graceful exit triggered by quantum back-reaction, and classical and quantum power spectra of density and metric perturbations.

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악기 종류에 따른 기능적인 연주복 디자인 연구 - 성인 여성의 하프 연주복을 중심으로 - (A Study on the Design of Functional Playing Costumes - focusing on Female Harpist -)

  • 여승화;정삼호
    • 복식
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    • 제54권4호
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    • pp.75-84
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    • 2004
  • Stage costumes perform not only the instrumental but also the expressive functions. The major goal of this study is to develop the functional and aesthetic costume designs for musical players considering the characteristics of instruments. players’ postures. The scope of this study is restricted to the musical costumes for female adult soloists playing the wind and string instruments. This study is composed of theory research, empiricalresearch and manufacturing a real costume. First, theory research contains theory of musical costumes and that of pure musical areas. Concept, characteristics and wearing effects are analysed in theory of musical costumes. Second, designs of instruments and playing postures are analysed in the theory of pure musical areas. Proper and improper designs are compared based on the survey asking the favorite designs of 56 wind and string players. Third, I manufacture a stage costume for a harpist. The conclusions of this study are as follows. First, wind and string players think the functionality of costumes more importantly than the esthetic sense. And there are differences in design preferences for different playing postures. Second, string Players basically use arms, fingers and the upper body. Wind players use fingers more than string players and do abdominal breathing. Third, string players think the design of arms and sleeves because of frequent usage of bow and prefer the design without sleeves. On the contrary, wind players think the silhouette importantly because of standing playing posture. Fourth, players don't think that the accessory is not important and want it so long as it doesn't hinder playing. Fifth, shoes plays more important role than costume in case of playing posture with using pedals and moving legs frequently. Lastly, both wind and string players prefer the design with simplicity and comfort most.

사진측량 기반 동영상 동특성 추출 (Photogrammetry-based Modal Parameter Extraction from Motion Pictures)

  • 김병화;여금수;김수진
    • 한국소음진동공학회논문집
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    • 제20권3호
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    • pp.308-315
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    • 2010
  • This study introduces a new technique to estimate modal parameters of a vibrating string using motion pictures. The approach requires two motion pictures for a vibrating string captured simultaneously by typical potable digital cameras or camcorders. Applying the space intersection theory and the space resection theory in photogrammetry, the steroscopic images for the string are constructed from two flat plane pictures. Then the three dimensional displacement components of the string are extracted by a multiple template matching technique. Finally the modal parameters of the string are estimated from the resulting displacement time histories. The accuracy of the approach has been examined through a small-scale mock-up of a string.

외부 메모리에서 문자열을 효율적으로 탐색하기 위한 인덱스 자료 구조 (An Index Data Structure for String Search in External Memory)

  • 나중채;박근수
    • 한국정보과학회논문지:시스템및이론
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    • 제32권11_12호
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    • pp.598-607
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    • 2005
  • 본 논문에서는 새로운 외부 메모리 인덱스 자료 구조인 접미사 B-tree를 제안한다. 접미사 B-tree는 String B-tree와 마찬가지로 문자열을 키로 가지는 B-tree이다. String B-tree의 노드는 복잡한 Patricia ie로 구현된 반면, 접미사 B-tree의 노드는 일반적인 B-tree처럼 배열로 구현되어 보다 간단하고 구현하기 쉽다. 그럼에도 불구하고 접미사 B-tree에서 배열을 이용하여 String B-tree만큼 효율적으로 분기를 찾을 수 있다. 결과적으로 문자열 알고리즘 분야에서 기본적이고 중요한 문제인 문자열 매칭을 String B-tree와 동일한 디스크 접근을 사용하여 수행할 수 있다.

다산의 악수설에 관한 연구 (A Study on Woosu Theory of Tasan Chung, Yak-yong)

  • 임영자;순남숙
    • 복식
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    • 제50권2호
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    • pp.5-13
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    • 2000
  • Woosu is the last process in the preparation of the deceased for burial. There are tow hypotheses on the purpose of Woosu. One is that it is to cover hands. The other is that it connects both arms of th body. The pattern of Woosu is 1 cheok 2 chon in length and 5 chon in width. The length is divided intc 3 parts equally with 4 chon. And then, it will be cutted 1 chon both sides of the middle part in Woosu. So, the width of middle part become 3 chon. Regarding the string used in soosu, two applications have been hypothesised . One is that each string is at both sides, the other is that each string ist at 4 edge respectively. Also there are two hypotheses about number of strings in Woosu. One is that total number of Woosu is one. The other is that the total number of Woosu is two. During the period of the Chosun dynasty, it is acknowledged that Sagye Kim, Jang-Saeng insisted that string of woosu is at one by one at both arms and hands respectively to be useful to cover hands of the body. But again the great scholar Tasan Chung, Yak-young pointed out that there are some problems on the explanatory notes and annotations of Sasangrye which ar quoted by Sagye Kim. Jang-Saeng. He insisted that the purpose of Woosu is to connect both arms using one string. Therefore, I will explain the intrinsic nature of Woosu by researching Tasan Chung , Yak-yong's Woosu theory.

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Nonlinear self-induced vibration and operability envelope analysis of production strings in marine natural gas development

  • Liu, Kang;Chen, Guoming;Zhu, Gaogeng;Zhu, Jingyu
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제11권1호
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    • pp.344-352
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    • 2019
  • Marine production strings are continuously affected by unstable internal fluid during operation. In this paper, the structural governing equation for marine production string self-induced vibration is constructed. A finite element analysis model is established based on Euler-Bernoulli theory and solved by the Newmark method. Furthermore, based on reliability theory, a self-design procedure is developed to determine the operability envelope for marine production string self-induced vibration. Case studies show: the response frequency of the production strings is consistent with the excitation frequency under harmonic fluctuation and mainly determined by the first-order natural frequency under stochastic fluctuation. The operability envelope for marine production string self-induced vibration is a near symmetrical trapezium. With the increasing of natural gas output, the permissible fluctuation coefficient dramatically decreases. A reasonable centralizer spacing, increasing top tension, and controlling natural gas output are of great significance to the risk control in marine production string operation.

Developing JSequitur to Study the Hierarchical Structure of Biological Sequences in a Grammatical Inference Framework of String Compression Algorithms

  • Galbadrakh, Bulgan;Lee, Kyung-Eun;Park, Hyun-Seok
    • Genomics & Informatics
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    • 제10권4호
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    • pp.266-270
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    • 2012
  • Grammatical inference methods are expected to find grammatical structures hidden in biological sequences. One hopes that studies of grammar serve as an appropriate tool for theory formation. Thus, we have developed JSequitur for automatically generating the grammatical structure of biological sequences in an inference framework of string compression algorithms. Our original motivation was to find any grammatical traits of several cancer genes that can be detected by string compression algorithms. Through this research, we could not find any meaningful unique traits of the cancer genes yet, but we could observe some interesting traits in regards to the relationship among gene length, similarity of sequences, the patterns of the generated grammar, and compression rate.

A SURVEY OF N-STRING TANGLE ANALYSES OF DNA-ENZYME SYNAPTIC COMPLEXES

  • KIM, SOOJEONG;MOON, HYEYONG
    • Journal of applied mathematics & informatics
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    • 제35권3_4호
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    • pp.349-369
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    • 2017
  • In last 30 years, mathematical tangle theory is applied to molecular biology, especially to DNA topology. The recent issues and research results of this topic are reviewed in this paper. We introduce a tangle which models an enzyme-DNA complex. The studies of 2-string tangle equations related to Topoisomerase II action and site-specific recombination is discussed. And 3-string tangle analysis of Mu-DNA complex, n-string tangle analysis ($n{\geq}4$) of DNA-enzyme synaptic complexes are also discussed.

Sensitivity of resistance forces to localized geometrical imperfections in movement of drill strings in inclined bore-holes

  • Gulyayev, V.I.;Khudoliy, S.N.;Andrusenko, E.N.
    • Interaction and multiscale mechanics
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    • 제4권1호
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    • pp.1-16
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    • 2011
  • The inverse problem about the theoretical analysis of a drill string bending in a channel of an inclined bore-hole with localized geometrical imperfections is studied. The system of ordinary differential equations is first derived based on the theory of curvilinear flexible elastic rods. One can then use these equations to investigate the quasi-static effects of the drill string bending that may occur in the process of raising, lowering and rotation of the string inside the bore-hole. The method for numerical solution of the constructed equations is described. With the proposed method, the phenomenon of the drill column movement, its contact interaction with the bore-hole surface, and the frictional seizure can be simulated for different combinations of velocities, directions of rotation and axial motion of the string. Geometrical imperfections in the shape of localized smoothed breaks of the bore-hole axis line are considered. Some numerical examples are presented to illustrate the applicability of the method proposed.

전송선로 기반 탄현 모델 (Transmission Line Based Plucked String Model)

  • 이진걸
    • 한국음향학회지
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    • 제32권4호
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    • pp.361-368
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    • 2013
  • 진동하는 현의 성질을 나타내는 방법으로 반대 방향으로 진행하는 파가 현과 전송선로에 존재한다는 사실에 기초하여 현은 전송선로에 비유되어왔다. 이러한 비유에서 현의 강역(rigid end)과 변위는 각각 전송선로의 개방회로와 전류로 나타내어졌다. 그러나, 본 연구에서 강역과 변위는 각각 단락회로와 전압에 해당됨이 전송선로의 이론으로부터 밝혀졌고 이를 회로시뮬레이션으로 확인하였다. 이러한 발견에 기초하여 전송선로, 구분적 선형 전류원, 스위치들로 구성된 전송선로 기반 탄현 모델을 제안하였다. 임의로 선택된 지점에서의 전압과 전송선로 끝 극소 부분 양단에서 계산된 전압이 현의 성질을 지배하는 파동방정식의 차분형식(difference form)으로 구한 해당 지점에서 변위와 강역에서의 힘과 일치함을 보임으로서 제안한 모델이 정당함을 증명하였다. 또한, 제안된 모델의 현악기 및 관악기 모델링의 적용성을 제시하였다.