• Title, Summary, Keyword: u-map

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The difference of image quality using other radioactive isotope in uniformity correction map of myocardial perfusion SPECT (심근 관류 SPECT에서 핵종에 따른 Uniformity correction map 설정을 통한 영상의 질 비교)

  • Song, Jae hyuk;Kim, Kyeong Sik;Lee, Dong Hoon;Kim, Sung Hwan;Park, Jang Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.87-92
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    • 2015
  • Purpose When the patients takes myocardial perfusion SPECT using $^{201}Tl$, the operator gives the patients an injection of $^{201}Tl$. But the uniformity correction map in SPECT uses $^{99m}Tc$ uniformity correction map. Thus, we want to compare the image quality when it uses $^{99m}Tc$ uniformity correction map and when it uses $^{201}Tl$ uniformity correction map. Materials and Methods Phantom study is performed. We take the data by Asan medical center daily QC condition with flood phantom including $^{201}Tl$ 21.3 kBq/mL. After postprocessing with this data, we analyze CFOV integral uniformity(I.U) and differential uniformity(D.U). And we take the data with Jaszczak ECT Phantom by American college of radiology accreditation program instruction including $^{201}Tl$ 33.4 kBq/mL. After post processing with this data, we analyze spatial Resolution, Integral Uniformity(I.U), coefficient of variation(C.V) and Contrast with Interactive data language program. Results In the flood phantom test, when it uses $^{99m}Tc$ uniformity correction map, Flood I.U is 3.6% and D.U is 3.0%. When it uses $^{201}Tl$ uniformity correction map, Flood I.U is 3.8% and D.U is 2.1%. The flood I.U is worsen about 5%, but the D.U is improved about 30% inversely. In the Jaszczak ECT phantom test, when it uses $^{99m}Tc$ uniformity correction map, SPECT I.U, C.V and contrast is 13.99%, 4.89% and 0.69. When it uses $^{201}Tl$ uniformity correction map, SPECT I.U, C.V and contrast is 11.37%, 4.79% and 0.78. All of data are improved about 18%, 2%, 13% The spatial resolution was no significant changes. Conclusion In the flood phantom test, Flood I.U is worsen but Flood D.U is improved. Therefore, it's uncertain that an image quality is improved with flood phantom test. On the other hand, SPECT I.U, C.V, Contrast are improved about 18%, 2%, 13% in the Jaszczak ECT phantom test. This study has limitations that we can't take all variables into account and study with two phantoms. We need think about things that it has a good effect when doctors decipher the nuclear medicine image and it's possible to improve the image quality using the uniformity correction map of other radionuclides other than $^{99m}Tc$, $^{201}Tl$ when we make other nuclear medicine examinations.

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On the continuity of the map induced by scalar-input control system

  • Shin, Chang-Eon
    • Communications of the Korean Mathematical Society
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    • v.11 no.3
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    • pp.695-706
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    • 1996
  • In the control system $ \dot{x} = f(t,x(t)) + g(t,x(t))\dot{u}, x(0) = \bar{x}, t \in [0,T], $ this paper shows that the map from u with $L^1(m)$-topology to $x_u$ with $L^1(\mu)$-topology is Lipschitz continuous where f is $C^1$, $\mu$ is the Stieltjes measure derived from the function g which is not smooth in the variable t and $x_u$ is the solution of the above system corresponding to u under the assumption that $\dot{u}$ is bounded.

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PROPER RATIONAL MAP IN THE PLANE

  • Jeong, Moon-Ja
    • The Pure and Applied Mathematics
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    • v.2 no.2
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    • pp.97-101
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    • 1995
  • In [6], the author studied the property of the Szeg kernel and had a result that if $\Omega$ is a smoothly bounded domain in C and the Szeg kernel associated with $\Omega$ is rational, then any proper holomorphic map from $\Omega$ to the unit disc U is rational. It leads to the study of the proper rational map of $\Omega$ to U. In this note, first we simplify the proof of the above result and prove an existence theorem of a proper rational map. Before we proceed to state our result, we must recall some preliminary facts.(omitted)

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Motion Field Estimation Using U-disparity Map and Forward-Backward Error Removal in Vehicle Environment (U-시차 지도와 정/역방향 에러 제거를 통한 자동차 환경에서의 모션 필드 예측)

  • Seo, Seungwoo;Lee, Gyucheol;Lee, Sangyong;Yoo, Jisang
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.12
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    • pp.2343-2352
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    • 2015
  • In this paper, we propose novel motion field estimation method using U-disparity map and forward-backward error removal in vehicles environment. Generally, in an image obtained from a camera attached in a vehicle, a motion vector occurs according to the movement of the vehicle. but this motion vector is less accurate by effect of surrounding environment. In particular, it is difficult to extract an accurate motion vector because of adjacent pixels which are similar each other on the road surface. Therefore, proposed method removes road surface by using U-disparity map and performs optical flow about remaining portion. forward-backward error removal method is used to improve the accuracy of the motion vector. Finally, we predict motion of the vehicle by applying RANSAC(RANdom SAmple Consensus) from acquired motion vector and then generate motion field. Through experimental results, we show that the proposed algorithm performs better than old schemes.

AN ENERGY DENSITY ESTIMATE OF HEAT EQUATION FOR HARMONIC MAP

  • Kim, Hyun-Jung
    • The Pure and Applied Mathematics
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    • v.18 no.1
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    • pp.79-86
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    • 2011
  • Suppose that (M,g) is a complete and noncompact Riemannian mani-fold with Ricci curvature bounded below by $-K{\leq}0$ and (N, $\bar{g}$) is a complete Riemannian manifold with nonpositive sectional curvature. Let u : $M{\times}[0,{\infty}){\rightarrow}N$ be the solution of a heat equation for harmonic map with a bounded image. We estimate the energy density of u.

GRADIENT ESTIMATE OF HEAT EQUATION FOR HARMONIC MAP ON NONCOMPACT MANIFOLDS

  • Kim, Hyun-Jung
    • Journal of applied mathematics & informatics
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    • v.28 no.5_6
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    • pp.1461-1466
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    • 2010
  • aSuppose that (M, g) is a complete Riemannian manifold with Ricci curvature bounded below by -K < 0 and (N, $\bar{b}$) is a complete Riemannian manifold with sectional curvature bounded above by a constant $\mu$ > 0. Let u : $M{\times}[0,\;{\infty}]{\rightarrow}B_{\tau}(p)$ is a heat equation for harmonic map. We estimate the energy density of u.

Effective Recognition of Land Registration Map Using Fuzzy Inference (퍼지추론 기반의 효율적인 지적도면 인식)

  • Kim, Yoon-Ho
    • The Journal of Advanced Navigation Technology
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    • v.11 no.3
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    • pp.343-349
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    • 2007
  • This paper addressed a recognition method of land registration map based on fuzzy inference scheme, which is able to solve the time complexity problem of typical method [Fig. 2]. Not only line color, thickness but also number, character are used as a fuzzy input parameter. It concentrated on generation of fuzzy association map, and useful informations are extracted result from fuzzy inference. These results are precedent process for estimating the construction space and restoring 3D automatic modeling. It can also utilize to the internet service acceleration propulsion business such as u-Gov based land registration service.

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A method of saving Digital Map which was made through Aerial Photography to ORDBMS (항공사진을 통해 제작된 수치지도의 ORDBMS 저장 방안)

  • Woo, Jae-Nam;Park, Hee-Soon;Kwon, Chang-Hee
    • The Journal of Advanced Navigation Technology
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    • v.13 no.6
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    • pp.831-837
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    • 2009
  • This paper suggests the method for saving the digital map which was made through aerial photography to ORDBMS (Object Relational Database Management System) and analyze its efficiency through experiments. The digital map has been used by file units because of managing or providing it to others. But this way can not get sequential graphic entities and just use it which was included in only one map. In this paper, we saved the digital map to ORDBMS at a time after converted the digital map entities based on the tile to the things can be inserted to ORDBMS. And, we also proved the possible methods to extract the graphic entities what we need from entire blueprint through experiments.

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SPACE-LIKE SURFACES WITH 1-TYPE GENERALIZED GAUSS MAP

  • Choi, Soon-Meen;Ki, U-Hang;Suh, Young-Jin
    • Journal of the Korean Mathematical Society
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    • v.35 no.2
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    • pp.315-330
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    • 1998
  • Chen and Piccinni [7] have classified all compact surfaces in a Euclidean space $R^{2+p}$ with 1-type generalized Gauss map. Being motivated by this result, the purpose of this paper is to consider the Lorentz version of the classification theorem and to obtain a complete classification of space-like surfaces in indefinite Euclidean space $R_{p}$ $^{2+p}$ with 1-type generalized Gauss map.p.

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A GENERALIZATION OF HOMOLOGICAL ALGEBRA

  • Davvaz, B.;Shabani-Solt, H.
    • Journal of the Korean Mathematical Society
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    • v.39 no.6
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    • pp.881-898
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    • 2002
  • Our aim in this paper is to introduce a generalization of some notions in homological algebra. We define the concepts of chain U-complex, U-homology, chain (U, U')-map, chain (U, U')-homotopy and $\mu$-functor. We also obtain some interesting results. We use these results to find a generalization of Lambek Lemma, Snake Lemma, Connecting Homomorphism and Exact Triangle.