• 제목/요약/키워드: conformal

검색결과 770건 처리시간 0.04초

Current status of proton therapy techniques for lung cancer

  • Han, Youngyih
    • Radiation Oncology Journal
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    • 제37권4호
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    • pp.232-248
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    • 2019
  • Proton beams have been used for cancer treatment for more than 28 years, and several technological advancements have been made to achieve improved clinical outcomes by delivering more accurate and conformal doses to the target cancer cells while minimizing the dose to normal tissues. The state-of-the-art intensity modulated proton therapy is now prevailing as a major treatment technique in proton facilities worldwide, but still faces many challenges in being applied to the lung. Thus, in this article, the current status of proton therapy technique is reviewed and issues regarding the relevant uncertainty in proton therapy in the lung are summarized.

저전압 VDMOS 의 ON-저항 모델링 (An Advanced On-Resistance Model for Low Voltage VDMOS)

  • 김성동;김일중;최연익;한민구
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1991년도 하계학술대회 논문집
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    • pp.166-170
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    • 1991
  • An advanced on-resistance model of VDMOS devices in the low voltage regime is proposed and verified by 2-D device simulations. The model considers the lateral gaussian doping profiles in the channel region and exact current spreading angles in the epitaxial layer for both linear and cellular geometries by employing the conformal mapping. It is found out that the on-resistance of low voltage VDMOS may be overestimated considerably if it is analyzed by the conventional method. The 2-D device simulation results show that the proposed model is valid for all ranges of cell spacings and breakdown voltages.

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Effect of Microstructure of Substrate on the Metallization Characteristics of the Electroless Copper Deposition for ULSI Interconnection Effect of Plasma

  • 홍석우;이용선;박종완
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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    • pp.86-86
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    • 2003
  • Copper has attracted much attention in the deep submicron ULSI metallization process as a replacement for aluminum due to its lower resistivity and higher electromigration resistance. Electroless copper deposition method is appealing because it yields conformal, high quality copper at relatively low cost and a low processing temperature. In this work, it was investigated that effect of the microstructure of the substrate on the electroless deposition. The mechanism of the nucleation and growth of the palladium nuclei during palladium activation was proposed. Electroless copper deposition on TiN barriers using glyoxylic acid as a reducing agent was also investigated to replace toxic formaldehyde. Furthermore, electroless copper deposition on TaN$\sub$x/ barriers was examined at various nitrogen flow rate during TaN$\sub$x/ deposition. Finally, it was investigated that the effect of plasma treatment of as-deposited TaN$\sub$x/ harriers on the electroless copper deposition.

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선형 격자 형성 방정식을 이용한 직교 격자 형성에 관한 연구 (Orthogonal Grid Generation Using Linear Grid Generating Equations)

  • 이상욱;권장혁;권오준
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2000년도 춘계 학술대회논문집
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    • pp.99-106
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    • 2000
  • A method of two and three dimensional orthogonal grid generation with control of spacing by using the covariant Laplace equation is Presented. An important feature of the methodology is its ability to control effectively the grid spacing especially near the boundaries still maintaining good orthogonality in whole field. The method is based on the concept of decomposition of the global transformation into consecutive transformation of an approximate conformal mapping and au auxiliary orthogonal mapping to have linear and uncoupled equations. Control of cell spacing is based on the concept of reference arc length, and orthogonal correction is performed in the auxiliary domain. It is concluded that the methodology can successfully generate well controlled orthogonal grids around bodies of 2 and 3 dimensional configurations.

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고온 회전 척을 구비한 포토레지스트 Spray Coating 방법 및 장치 (The Method and Apparatus for Photoresist Spray Coating with High Temperature Rotational Chuck)

  • 박태규;김준태;김국진;석창길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.42-44
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    • 2003
  • The paper presents the method and apparatus for conformal photoresist spray coating on the 3D structured substrate. The system consists of a high-temperature-rotational chuck, ultrasonic spray nozzle module, angle control module and nozzle moving module. The coating uniformity is acquired by controlling the moving speed of the ultrasonic spray nozzle across the substrate which is rotated constantly. To coat the photoresist conformally the spray angle of the nozzle and the temperature of the substrate are controlled during spray coating. The rotational chuck can be heated up by hot air or $N_2$. The photoresist (AZ1512) has been coated on the 3D structured wafer by spray coating system and the characteristics have been evaluated.

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일반 형상의 커프스형 강체균열에 대한 열응력세기계수 결정 (Determination of thermal Stress Intensity Factors for General Cusp-Crack Shaped Rigid Inclusion)

  • 이강용;장용훈
    • 대한기계학회논문집
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    • 제16권6호
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    • pp.1216-1220
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    • 1992
  • 본 연구에서는 Lee등의 연구를 일반화하기 위하여 급수 형태의 등각사상함수 로 표현되는 일반형태의 커스프형 강체함유물이 존재하는 경우에 대하여 복소 포텐셜 함수와 TSIF에 대한 일반해를 구하기로 한다.

원통면 음향 홀로그래피를 이용한 수중음향 곡면배열센서의 빔 해석 (Beam Analysis of Underwater Conformal Array by Using Cylindrical Acoustic Holography)

  • 권휴상;박성철;서희선;신구균;조치영
    • 한국소음진동공학회논문집
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    • 제19권10호
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    • pp.987-995
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    • 2009
  • As an experimental technique to analyze the far-field characteristics of underwater cylindrical array sensors, cylindrical acoustic holography is studied. Inside an laboratory water tank, far-field directivity patterns as well as near-field source images are reconstructed from the measured hologram by hydrophone array. Approximate equation for far-field directivity estimation is derived based on stationary phase method. The simulation and experiment show well usefulness of the proposed method in application of underwater array sensors.

Atomic Layer Deposition of $Sb_2S_3$ Thin Films on Mesoporous $TiO_2$

  • 한규석;정진원;성명모
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.282-282
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    • 2013
  • The antimony sulfide ($Sb_2S_3$) thin films were deposited using the gas phase method which known as atomic layer deposition (ALD) on mesoporous micro-films. Tris (dimethylamido) antimony (III[$(Me_2N)_3Sb$] and hydrogensulfide ($H_2S$) were used as precursors to deposit $Sb_2S_3$. Self-terminating nature of $(Me_2N)_3Sb$ and $H_2S$ reaction were demonstrated by growth rate saturation versus precursors dosing time. Absorption spectra and extinction coefficient were investigated by UV-VIS spectroscopy. Scanning electron microscopic analysis and X-ray photoelectron spectroscopy (XPS) depth profile were employed to determine the conformal deposition.

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Shape factors of cylindrical permeameters

  • Silvestri, Vincenzo;Samra, Ghassan Abou;Bravo-Jonard, Christian
    • Geomechanics and Engineering
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    • 제3권1호
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    • pp.17-28
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    • 2011
  • This paper presents an analytical solution for steady state flow into a close-ended cylindrical permeameter. The soil medium is considered to be uniform, isotropic, and of infinite thickness. Laplace equation is solved by considering rotational symmetry and by using curvilinear coordinates obtained from conformal mapping. The deduced shape factors, which are compared to approximate relationships obtained from both numerical and physical modelling, and idealizations involving ellipsoidal cavities, are proposed for use in field measurements. It is shown that some of the shape factors obtained are significantly different from published values and show a much higher dependence of the rate of flow on the aspect ratio, than deduced from approximate solutions.

TRANSVERSE HARMONIC FIELDS ON RIEMANNIAN MANIFOLDS

  • Pak, Jin-Suk;Yoo, Hwal-Lan
    • 대한수학회보
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    • 제29권1호
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    • pp.73-80
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    • 1992
  • We discuss transverse harmonic fields on compact foliated Riemannian manifolds, and give a necessary and sufficient condition for a transverse field to be a transverse harmonic one and the non-existence of transverse harmonic fields. 1. On a foliated Riemannian manifold, geometric transverse fields, that is, transverse Killing, affine, projective, conformal fields were discussed by Kamber and Tondeur([3]), Molino ([5], [6]), Pak and Yorozu ([7]) and others. If the foliation is one by points, then transverse fields are usual fields on Riemannian manifolds. Thus it is natural to extend well known results concerning those fields on Riemannian manifolds to foliated cases. On the other hand, the following theorem is well known ([1], [10]): If the Ricci operator in a compact Riemannian manifold M is non-negative everywhere, then a harmonic vector field in M has a vanishing covariant derivative. If the Ricci operator in M is positive-definite, then a harmonic vector field other than zero does not exist in M.

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