• Title/Summary/Keyword: pre-sphere

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On irreducible 3-manifolds

  • Lee, Jae-Ik
    • Communications of the Korean Mathematical Society
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    • v.12 no.4
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    • pp.1023-1032
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    • 1997
  • This paper deals with certain conditions under which irreducibility of a 3-manifold is preserved under attaching a 2-handle along a simple closed curve (and then, if necessary, capping off a 2-sphere boundary component by a 3-ball).

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The Dynamical Models of the Life Action on the Assimilation and Dissimilation in the Ecosystem (생태계에 있어서 동화.이화작용에 관한 동력학적 모델)

  • 장남기
    • Asian Journal of Turfgrass Science
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    • v.10 no.4
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    • pp.331-339
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    • 1996
  • The mass action on the assimilation and dissimilation of a living system from bio-molecules to bio-spheres has been demonstrated by the theoretical models as the bio- and trophic-functions From the viewpoint of this bio-mechanics, the general principle on the pre-equilibrium of the bio-molecular system is found. Key words: Mass action, Living system, Bio-molecule, Bio-sphere, Bio- and trophic function.

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Rate Capability of Electric Double-Layer Capacitor (EDLC) Electrodes According to Pore Length in Spherical Porous Carbons

  • Ka, Bok-H.;Yoon, Song-Hun;Oh, Seung-M.
    • Journal of the Korean Electrochemical Society
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    • v.10 no.4
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    • pp.252-256
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    • 2007
  • A series of spherical porous carbons were prepared via resorcinol-formaldehyde (RF) sol-gel polymerization in the presence of cationic surfactant (CTAB, cetyltrimethylammonium bromide), wherein the carbon sphere size was controlled by varying the CTAB introduction time after a pre-determined period of addition reaction (termed as "pre-curing"). The sphere size gradually decreases with an increase in the pre-curing time within the range of 30-150 nm. The carbons possess two types of pores; one inside carbon spheres (intra-particle pores) and the other at the interstitial sites made by carbon spheres (inter-particle pores). Of the two, the surface exposed on the former was dominant to determine the electric double-layer capacitor (EDLC) performance of porous carbons. As the intra-particle pores were generated inside RF gel spheres by gasification, the pore diameter was similar for all these carbons, thereby the pore length turned out to be a decisive factor controlling the EDLC performance. The charge-discharge voltage profiles and complex capacitance analysis consistently illustrate that the smaller-sized RF carbons deliver a better rate capability, which must be the direct result of facilitated ion penetration into shorter pores.

Effect of Pre-Aging Conditions on Bake-Hardening Response of Al-0.4 wt%Mg-1.2 wt%Si-0.1 wt%Mn Alloy Sheets

  • Lee, Kwang-jin;Woo, Kee-do
    • Korean Journal of Metals and Materials
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    • v.49 no.6
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    • pp.448-453
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    • 2011
  • Pre-aging heat treatment after solution heat treatment (SHT) of Al-0.4 wt%Mg-1.2 wt%Si-0.1 wt%Mn alloy sheets for auto-bodies was carried out to investigate the effect of pre-aging and its conditions on the bake-hardening response. Mechanical properties were evaluated by a tensile and Vickers hardness test. Microstructural observation was also performed using a transmission electron microscope (TEM). It was revealed that pre-aging treatments play a great role in the bake-hardening response. In addition, it was found that the sphere-shaped nanosized clusters that can directly transit to the needle-shaped ${\beta}$" phase during the paint-bake process, not being dissolved into the matrix, are formed at 343 K. The result, reveals that the dominant factor of the bake-hardening response is the pre-aging temperature rather than the pre-aging time.

Design and Characteristic Measurement of 8000 mm Large Aperture Integrating Sphere

  • Zhang, Zhao;Wan, Zhi;Li, Xiansheng;Liu, Hongxing;Sun, Jingxu;Liu, Zexun;Wang, Yamin;Ren, Jianwei;Ren, Jianyue
    • Journal of the Optical Society of Korea
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    • v.20 no.4
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    • pp.500-509
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    • 2016
  • Integrating spheres play a central role in the radiometric calibration of remote sensors. With the development of the wide field of view (FOV) remote sensors, aperture diameters of remote sensors are becoming larger and larger. To satisfy the radiometric calibration requirements of full FOV and full aperture, an 8000mm diameter large aperture integrating sphere uniform source with a variable exit port was designed and manufactured. This integrating sphere will be used for pre-launch test and radiometric calibration of remote satellites. In this paper, optical theories were used to design the output spectral radiance. The LightTools software based on ray-tracing simulation method was used to determine the best combination and distribution of inner light sources. A spectral experiment was made to verify the spectral radiance design. To reduce the influence of longtime power-on, a new characteristic measurement method was developed to obtain the radiation characteristic of the integrating sphere, which could greatly improve the measuring efficiency. This method could also be applied to measure other large aperture uniform sources. The obtained results indicate that the spatial uniformity is 98.35%, and the angular uniformity at center position is 98.78%.

Investigation of the optimum condition for the quantitative analysis of Cu sample by Laser induced breakdown spectroscopy (구리 시료의 정량분석을 위한 LIBS의 최적조건 연구)

  • Kim, Seunghyun;Shin, Heesung;Ju, Junesik;Kim, Hodong
    • Analytical Science and Technology
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    • v.22 no.2
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    • pp.141-147
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    • 2009
  • A laser induced breakdown spectroscopy (LIBS) measurement was carried out to derive an optimized measurement condition with a high reproducibility and to grow a plasma sphere to 20 mm high under a 600 mtorr vacuum in order to improve an accuracy of measurement. The measurement of the plasma was taken at a 6.0 mm distance, in the direction of a plasma sphere, from a sample. This location belongs to the outer sphere region in the plasma. The calibration curve of 'Ni' and 'Cu' was acquired by the signal intensity ratio and the atomic ratio for the samples, and linear regression of 'Cu' was $R^2$=0.9886, and the linear regression of 'Ni' was $R^2$=0.9988. The accuracy of LIBS was improved pre-existence as the measurement error of 'Ni' was 0.78%.

Phase Behaviors of Binary Protein Systems: Consideration of Structural Effects

  • Kim, Sang-Gon;Kong, Sung-Ho;Bae, Young-Chan;Kim, Sun-Joon
    • Macromolecular Research
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    • v.11 no.4
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    • pp.241-249
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    • 2003
  • A molecular-thermodynamic model to describe the salt-induced protein precipitation is developed based on the perturbation theory. We employed the modified perturbed hard-sphere-chain (PHSC) equation of state for copolymer mixtures to take into account the pre-aggregation effect among protein particles. Hypothetical pressure-composition diagrams are computed with various size differences and salt concentrations. The precipitation behaviors are also studied for various types of pre-aggregation effect for the given systems.

Visualization of 4-Dimensional Scattered Data Linear Interpolation Based on Data Dependent Tetrahedrization (4차원 산포된 자료 선형 보간의 가시화 -자료 값을 고려한 사면체 분할법에 의한-)

  • Lee, Kun
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.6
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    • pp.1553-1567
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    • 1996
  • The numerous applications surface interpolation include the modeling and visualization phenomena. A tetrahedrization is one of pre-processing steps for 4-D space interpolation. The quality of a piecewise linear interpolation 4-D space depends not only on the distribution of the data points in $R^2$, but also on the data values. We show that the quality of approximation can be improved by data dependent tetraheadrization through visualization of 4-D space. This paper discusses Delaunary tetrahedrization method(sphere criterion) and one of the data dependent tetrahedrization methods(least squares fitting criterion). This paper also discusses new data dependent criteria:1) gradient difference, and 2) jump in normal direction derivative.

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Humor of Post-Industrial Society Costume Expressing Cartoon Image (만화 이미지가 표현된 후기산업사회 복식의 해학)

  • 류근영;이효진
    • Journal of the Korean Society of Costume
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    • v.52 no.8
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    • pp.55-71
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    • 2002
  • The purpose of this study was to identify a basic meaning of humor from the costume expressing cartoon image, to grasp the status of contemporary costume, and also to supply people with a database related to the sphere of costume design. This was done by analyzing and examining humor of the costume expressing cartoon image in post-industrial society. Consequently, the result of this study was summarized as follows; First, humor by parody of Pop Art is recognized as humorous expression that repulsed the main current culture and post-industrial society phenomenon. Second, humor by quotation tends to appear through cartoon character. Costume which quote cartoon character is against Kidult tastes and the pre-existing authoritative prejudices in post-industrial society. Third, humor by bricolage, making bricolage with silhouette, color, pattern item, is recognized as new creation of humor In other words, it is regarded as enlargement of new esthetic consciousness and humor about instrumented gender in post-industrial society. Lastly, humor by deformation expressed itself in deformation of body image of character and cloth silhouette by cartoon image. Deformation of cloth silhouette by cartoon image, being not conscious pre-existing concept of harmony of human and costume, is recognized as humor which have characteristic of play with introduction of new silhouette. In addition to, the result of this study showed that humor expressed in cartoon image of costume has been limited to the works of few designers because of characteristics of fashion designers who made use of popularity as subjects of the works and internal meanings which were related to the characteristics of post-industrial society.

Recognition of surface orientations in an object using photomeric stereo method (포토메트릭 스테레오를 이용한 물체표면방향의 인식)

  • 이종훈;전태현;김도성;이명호
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.816-820
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    • 1990
  • This paper is pre-stage for getting EGI which can be used for modeling of an object. It discusses the construction of the vision processing system and its algorithm for getting needle diagram from tie object image. We realize the algorithm with monocular camera system, using Reflectance Map theory and photometric stereo method. We can calculate the surface normal at any point in the image if we take multiple images at the different lighting conditions. From the 3 images taken from different lighting conditions through the experiment, we get the needle diagrams of the sphere and the object. We confirm the validness of the surface, normal acquisition algorithm comparing the experimental needle diagram with the ideal one obtained from the surface normal of the known object.

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