• 대한수학회지
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• 제48권1호
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• pp.1-12
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• 2011

The purpose of this paper is to study pseudo-Riemannian algebras, which are algebras with pseudo-Riemannian non-degenerate symmetric bilinear forms. We nd that pseudo-Riemannian algebras whose left centers are isotropic play a curial role and show that the decomposition of pseudo-Riemannian algebras whose left centers are isotropic into indecomposable non-degenerate ideals is unique up to a special automorphism. Furthermore, if the left center equals the center, the orthogonal decomposition of any pseudo-Riemannian algebra into indecomposable non-degenerate ideals is unique up to an isometry.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.948-949
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• 2006

An infiltration technique using W-Cu composite powder has been developed to enhance microstructural uniformity of W-Cu pseudo-alloy. W-Cu composite powder, manufactured by reduction from $WO_3$ and CuO powder mixtures, were blended with W powder and then cold iso-statically pressed into a cylindrical bar under 150 MPa. The pressed samples were pre-sintered at $1300^{\circ}C$ for 1 hour under hydrogen to make a skeleton structure. This skeleton structure was more homogeneous than that formed by using W and Cu powder mixtures. The skeleton structures were infiltrated with Cu under hydrogen atmosphere. The infiltrated W-Cu pseudo-alloy showed homogeneous microstructure without Cu rich region

• Structural Engineering and Mechanics
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• 제24권1호
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• pp.91-105
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• 2006

In this paper, post-earthquake capacity evaluation method of reinforced concrete buildings was studied. Substructure pseudo-dynamic test and static loading test of first story column in a four-story R/C building was carried out in order to investigate the validity of the evaluation method proposed in the Damage Assessment Guideline (JBDPA 2001). In pseudo-dynamic test, different levels of damage were induced in the specimens by pre-loading, and input levels of seismic motion, at which the specimens reached to the ultimate stage, were examined. From the experimental result, no significant difference in damage levels such as residual crack width between the specimens under static and pseudo-dynamic loading was found. It is shown that the seismic capacity reduction factors ${\eta}$ can provide a reasonable estimation of post-earthquake seismic capacity of R/C buildings suffered earthquakes.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.16-16
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• 2000

This paper describes a new structure re create a pseudo Gaussian function network (PGFN). The activation function of hidden layer does not necessarily have to be symmetric with respect to center. To give the flexibility of the network, the deviation of pseudo Gaussian function is changed according to a direction of given input. This property helps that given function can be described effectively with a minimum number of center by PGFN, The distribution of deviation is represented by level set method and also the loaming of deviation is adjusted based on it. To demonstrate the performance of the proposed network, general problem of function estimation is treated here. The representation problem of continuous functions defined over two-dimensional input space is solved.

• Journal of Radiation Protection and Research
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• 제26권4호
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• pp.417-424
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• 2001

세기 조절 방사선 치료 최적화 대상 함수로 이용하기 위하여 유사 생물학적 대상 함수를 고안하여, 그 가능성을 살펴보았다. 치료 계획 장치는 본 연구진이 개발한 RTP Tool Box(RTB)를 사용하였다. 수학적으로 생물학적 대상 함수와 비슷하나, 사용하는 상수들은 물리적인 인자를 사용한 유사 생물학적(Pseudo-biologic) 대상 함수를 도입하였다. 치료하고자 하는 표적에 대하여는 표적 포함인자(TCI, Target Coverage Index) 개념을 도입하였고, 정상 장기에 대해서는 조직성적 인자(OSI, Organ Score Index) 개념을 도입하였다. 또한 TCI와 OSI 개념을 사용하여 대상함수 S를 정의하였다. 어떤 종류의 대상 함수를 사용하든 표적 선량의 분포는 비슷한 추세를 보였으나, 유사 생물학적 대상 함수를 사용한 경우 정상 조직의 선량 분포가 물리적인 대상 함수를 사용한 치료 계획보다 낮게 나와 세기조절 방사선 치료의 대상 함수로 사용할 수 있음을 보였다.

• 한국유변학회:학술대회논문집
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• 한국유변학회 2002년도 춘계 학술발표회 논문집
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• pp.65-68
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• 2002

• 대한수학회보
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• 제61권3호
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• pp.867-873
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• 2024

A pseudo-Riemannian solvmanifold is a solvable Lie group endowed with a left invariant pseudo-Riemannian metric. In this short note, we investigate the nilpotency of the Ricci operator of pseudo-Riemannian solvmanifolds. We focus on a special class of solvable Lie groups whose Lie algebras can be expressed as a one-dimensional extension of a nilpotent Lie algebra ℝD⋉n, where D is a derivation of n whose restriction to the center of n has at least one real eigenvalue. The main result asserts that every solvable Lie group belonging to this special class admits a left invariant pseudo-Riemannian metric with nilpotent Ricci operator. As an application, we obtain a complete classification of three-dimensional solvable Lie groups which admit a left invariant pseudo-Riemannian metric with nilpotent Ricci operator.

• BMB Reports
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• 제44권2호
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• pp.118-122
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• 2011

Most widely used secondary structure assignment methods such as DSSP identify structural elements based on N-H and C=O hydrogen bonding patterns from X-ray or NMR-determined coordinates. Secondary structure assignment algorithms using limited $C{\alpha}$ information have been under development as well, but their accuracy is only ~80% compared to DSSP. We have hereby developed SABA (Secondary Structure Assignment Program Based on only Alpha Carbons) with ~90% accuracy. SABA defines a novel geometrical parameter, termed a pseudo center, which is the midpoint of two continuous $C{\alpha}s$. SABA is capable of identifying $\alpha$-helices, $3_{10}$-helices, and $\beta$-strands with high accuracy by using cut-off criteria on distances and dihedral angles between two or more pseudo centers. In addition to assigning secondary structures to $C{\alpha}$-only structures, algorithms using limited $C{\alpha}$ information with high accuracy have the potential to enhance the speed of calculations for high capacity structure comparison.

• 한국초전도ㆍ저온공학회논문지
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• 제18권2호
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• pp.14-17
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• 2016

Annealing as-grown electron-doped cuprates under a low oxygen-partial-pressure condition is a necessary step to achieve superconductivity. It has been recently found that the so-called protect annealing results in much better superconducting properties in terms of the superconducting transition temperature and volume fraction. In this article, we report on angle-resolved photoemission spectroscopy studies of a protect-annealed electron-doped cuprate $Pr_{0.9}La_{1.0}Ce_{0.1}CuO_4$ on annealing condition dependent superconducting and pseudo-gap properties. Remarkably, we found that the one showing a better superconducting property possesses almost no pseudo-gap while others have strong pseudo-gap feature due to an anti-ferromagnetic order.

• 한국ITS학회 논문지
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• 제10권6호
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• pp.84-90
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• 2011

본 논문은 이중대역 Pseudo-combline 협대역 대역통과 여파기를 제안한다. 제안한 이중대역 대역통과 여파기의 특징은 개방형 공진 스터브를 사용하고 있으며 ITS와 X-밴드 위성 시스템에 적용이 가능하다. 이중대역 대역통과 여파기는 첫번째 운용 주파수 대역의 중심 주파수 5.8 GHz 그리고 대역폭 3.6 %에서 삽입 및 반사 손실이 각각 1.72 dB 및 15.5 dB 이다. 또한 두 번째 운용 주파수 대역의 중심 주파수 8.5 GHz 그리고 대역폭 3%에서 삽입 및 반사 손실은 각각 1.92 dB 및 16.3 dB 이다.