• Title/Summary/Keyword: preserve

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DIFFUSION PIECEWISE HOMOGENIZATION VIA FLUX DISCONTINUITY RATIOS

  • Sanchez, Richard;Dante, Giorgio;Zmijarevic, Igor
    • Nuclear Engineering and Technology
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    • v.45 no.6
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    • pp.707-720
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    • 2013
  • We analyze piecewise homogenization with flux-weighted cross sections and preservation of averaged currents at the boundary of the homogenized domain. Introduction of a set of flux discontinuity ratios (FDR) that preserve reference interface currents leads to preservation of averaged region reaction rates and fluxes. We consider the class of numerical discretizations with one degree of freedom per volume and per surface and prove that when the homogenization and computing meshes are equal there is a unique solution for the FDRs which exactly preserve interface currents. For diffusion submeshing we introduce a Jacobian-Free Newton-Krylov method and for all cases considered obtain an 'exact' numerical solution (eight digits for the interface currents). The homogenization is completed by extending the familiar full assembly homogenization via flux discontinuity factors to the sides of regions laying on the boundary of the piecewise homogenized domain. Finally, for the familiar nodal discretization we numerically find that the FDRs obtained with no submesh (nearly at no cost) can be effectively used for whole-core diffusion calculations with submesh. This is not the case, however, for cell-centered finite differences.

Neoadjuvant Chemotherapy and Radiotherapy in the Treatment of Advanced Head and Neck Cancer : Protocol Based Study (진행성 두경부암에서 선행항암요법과 방사선요법의 치료성적)

  • Kim Chul-Ho;Choi Jin-Hyuk;Lee Jin-Seok;Oh Young-Taek
    • Korean Journal of Head & Neck Oncology
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    • v.20 no.2
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    • pp.172-176
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    • 2004
  • Background and Objectives: Standard treatment of locally advanced laryngeal, hypopharyngeal, and some oropharyngeal cancers includes total laryngectomy. In an attempt to preserve the larynx through induction chemotherapy, we designed induction chemotherapy followed by definitive radiation in patients with potentially respectable head and neck cancer to determine whether organ preservation is feasible without apparent compromise of survival. Materials and Methods: The twenty-six patients diagnosed advanced head and neck squamous cell carcinoma, Stage III or IV (AJCC 2002) and performed organ preservation protocols in Ajou university hospital from 1994 to 2001 were included in this study. Results: Neoadjuvant chemotherapy showed an overall response rate of 84.6% and a complete remission (CR) rate was 59.1% following neoadjuvant chemotherapy and radiation. Seven of thirteen patients were able to preserve their larynges for more than two years by chemotherapy and radiation. There were no treatment related mortality after 2 cycles of induction chemotherapy. Conclusion: Although Organ preservation protocol through neoadjuvant chemotherapy and radiation need more controlled randomized study, it was considered alternative treatment modality in advanced head and neck cancer.

A Fast and Secure Method to Preserve Anonymity in Electronic Voting (전자투표에서 익명성 보장을 위한 빠르고 안전한 방식)

  • Yang, Hyung-Kyu
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.245-251
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    • 2014
  • Mix network plays a key role in electronic voting to preserve anonymity and lots of mixnet schemes have been proposed so far. However, they requires complex and costly zero-knowledge proofs to provide their correct mixing operations. In 2010, Seb$\acute{e}$ et al. proposed an efficient and lightweight mixnet scheme based on a cryptographic secure hash function instead of zero-knowledge proofs. In this paper, we present a more efficient and faster mixnet scheme than Seb$\acute{e}$ et al.'s scheme under the same assumption. Also, our scheme is secure.

JPEG-2000 Gradient-Based Coding: An Application To Object Detection

  • Lee, Dae Yeol;Pinto, Guilherme O.;Hemami, Sheila S.
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2013.11a
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    • pp.165-168
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    • 2013
  • Image distortions, such as quantization errors, can have a severe negative impact on the performance of computer vision algorithms, and, more specifically, on object detection algorithms. State-of-the-art implementations of the JPEG-2000 image coder commonly allocate the available bits to minimize the Mean-Squared-Error (MSE) distortion between the original image and the resulting compressed image. However, considering that some state-of-the-art object detection methods use the gradient information as the main image feature, an improved object detection performance is expected for JPEG-2000 image coders that allocate the available bits to minimize the distortions on the gradient content. Accordingly, in this work, the Gradient Mean-Squared-Error (GMSE) based JPEG-2000 coder presents an improved object detection performance over the MSE based JPEG-2000 image coder when the object of interest is located at the same spatial location of the image regions with the strongest gradients and also for high bit-rates. For low bit-rates (e.g. 0.07bpp), the GMSE based JPEG-2000 image coder becomes overly selective in choosing the gradients to preserve, and, as a result, there is a greater chance of mismatch between the spatial locations of the gradients that the coder is trying to preserve and the spatial locations of the objects of interest.

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Primary repair of symptomatic neonates with tetralogy of Fallot with or without pulmonary atresia

  • Lee, Chang-Ha;Kwak, Jae Gun;Lee, Cheul
    • Clinical and Experimental Pediatrics
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    • v.57 no.1
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    • pp.19-25
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    • 2014
  • Recently, surgical outcomes of repair of tetralogy of Fallot (TOF) have improved. For patients with TOF older than 3 months, primary repair has been advocated regardless of symptoms. However, a surgical approach to symptomatic TOF in neonates or very young infants remains elusive. Traditionally, there have been two surgical options for these patients: primary repair versus an initial aortopulmonary shunt followed by repair. Early primary repair provides several advantages, including avoidance of shunt-related complications, early relief of hypoxia, promotion of normal lung development, avoidance of ventricular hypertrophy and fibrosis, and psychological comfort to the family. Because of advances in cardiopulmonary bypass techniques and accumulated experience in neonatal cardiac surgery, primary repair in neonates with TOF has been performed with excellent early outcomes (early mortality<5%), which may be superior to the outcomes of aortopulmonary shunting. A remaining question regarding surgical options is whether shunts can preserve the pulmonary valve annulus for TOF neonates with pulmonary stenosis. Symptomatic neonates and older infants have different anatomies of right ventricular outflow tract (RVOT) obstructions, which in neonates are nearly always caused by a hypoplastic pulmonary valve annulus instead of infundibular obstruction. Therefore, a shunt is less likely to preserve the pulmonary valve annulus than is primary repair. Primary repair of TOF can be performed safely in most symptomatic neonates. Patients who have had primary repair should be closely followed up to evaluate the RVOT pathology and right ventricular function.

A Study on Cascade Filter Algorithm for Random Valued Impulse Noise Elimination (랜덤 임펄스 잡음제거를 위한 캐스케이드 필터 알고리즘에 관한 연구)

  • Yinyu, Gao;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.3
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    • pp.598-604
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    • 2012
  • Image signal is corrupted by various noises in image processing, many studies are being accomplished to restore those images. In this paper, we proposed a cascade filter algorithm for removing random valued impulse noise. The algorithm consists two steps that noise detection and noise elimination. Variance of filtering mask and center pixel variance are calculated for noise detection, and the noise pixel is replaced by estimated value which first apply switching self adaptive weighted median filter and finally processed by modified weight filter. Considering the proposed algorithm only remove noise and preserve the uncorrupted information that the algorithm can not only remove noise well but also preserve edge.

Characterizations of Zero-Term Rank Preservers of Matrices over Semirings

  • Kang, Kyung-Tae;Song, Seok-Zun;Beasley, LeRoy B.;Encinas, Luis Hernandez
    • Kyungpook Mathematical Journal
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    • v.54 no.4
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    • pp.619-627
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    • 2014
  • Let $\mathcal{M}(S)$ denote the set of all $m{\times}n$ matrices over a semiring S. For $A{\in}\mathcal{M}(S)$, zero-term rank of A is the minimal number of lines (rows or columns) needed to cover all zero entries in A. In [5], the authors obtained that a linear operator on $\mathcal{M}(S)$ preserves zero-term rank if and only if it preserves zero-term ranks 0 and 1. In this paper, we obtain new characterizations of linear operators on $\mathcal{M}(S)$ that preserve zero-term rank. Consequently we obtain that a linear operator on $\mathcal{M}(S)$ preserves zero-term rank if and only if it preserves two consecutive zero-term ranks k and k + 1, where $0{\leq}k{\leq}min\{m,n\}-1$ if and only if it strongly preserves zero-term rank h, where $1{\leq}h{\leq}min\{m,n\}$.

An Improved Adaptive Median Filter for Impulse Noise Removal (임펄스 잡음 제거를 위한 개선된 적응 메디안 필터)

  • Long, Xu;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.4
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    • pp.989-995
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    • 2013
  • Image degradation caused by the impulse noise is generated in the process of image transmission and so on. It has been studied by many researchers in order to remove these noise. The representative impulse noise removal method includes SM filter. Though SM filter will indicate errors by the increasing of impulse noise density. Therefore, in this paper, in order to preserve the edges of the image, and reduce the distortion of the image, an improved adaptive median filter algorithm is proposed. In the simulation results, the algorithm showed excellent results in all several areas, and the PSNR is used as the criterion of evaluation.

Mapping Vegetation Volume in Urban Environments by Fusing LiDAR and Multispectral Data

  • Jung, Jinha;Pijanowski, Bryan
    • Korean Journal of Remote Sensing
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    • v.28 no.6
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    • pp.661-670
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    • 2012
  • Urban forests provide great ecosystem services to population in metropolitan areas even though they occupy little green space in a huge gray landscape. Unfortunately, urbanization inherently results in threatening the green infrastructure, and the recent urbanization trends drew great attention of scientists and policy makers on how to preserve or restore green infrastructure in metropolitan area. For this reason, mapping the spatial distribution of the green infrastructure is important in urban environments since the resulting map helps us identify hot green spots and set up long term plan on how to preserve or restore green infrastructure in urban environments. As a preliminary step for mapping green infrastructure utilizing multi-source remote sensing data in urban environments, the objective of this study is to map vegetation volume by fusing LiDAR and multispectral data in urban environments. Multispectral imageries are used to identify the two dimensional distribution of green infrastructure, while LiDAR data are utilized to characterize the vertical structure of the identified green structure. Vegetation volume was calculated over the metropolitan Chicago city area, and the vegetation volume was summarized over 16 NLCD classes. The experimental results indicated that vegetation volume varies greatly even in the same land cover class, and traditional land cover map based above ground biomass estimation approach may introduce bias in the estimation results.

A Literature Review of the Type and Cooking Methods for Gwapyeon during the Joseon Dynasty - with a focus on Euigwe and old literature - (조선시대 과편의 종류 및 조리방법에 대한 문헌적 고찰 - 의궤와 고문헌을 중심으로 -)

  • Oh, Soon-Duk
    • Journal of the Korean Society of Food Culture
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    • v.28 no.1
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    • pp.1-11
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    • 2013
  • This study examined the prevalence of the traditional fruit preserve, gwapyeon, recorded in 10 royal palace studies and 10 old literature reports on the Joseon dynasty (1392-1909). A total of 62 papers presented the Gwapyeon kind in the documents of the Joseon dynasty. The protocols of the court of the Joseon Dynasty and old literature discussed the Gwapyeon as follows: Nokmalbyeong (ohmijapyeon) 22.5%; aengdupyeon (櫻桃片) 14.5%; salgupyeon (杏) and bokbunjapyeon (覆盆子) at 11.3% each; beojjipyeon and mogwapyeon (木瓜) at 8.1% each; sansapyeon (山査) and chijapyeon at 6.5% each; duchungpyeon (杜沖) 4.8%; and deuljjukpyeon, saenggangpyeon (薑), daechupyeon (棗) and yujapyeon (柚子) at 1.6% each. From "Junghae-Jungraeeuigwe (丁亥整禮儀軌)" (1827) to "Junghae-Jinchaneuigwe (丁亥進饌儀軌)" (1887) called nokmalbyeong (菉末餠). "Sinchuk-Jinchaneuigwe (辛丑進饌儀軌)" (May 1901) renamed the ohmijabyeong (五味子餠). "Sinchuk-Jinyeoneuigwe (辛丑進宴儀軌)" (July 1901), the assorted-sulsilgwa (各色熟實果 ) were included in the ohmijabyeong. "Imin-Jinchaneuigwe (壬寅進饌儀軌)" (April 1902), The ohmijabyeong (五味子餠) and assorted-sulsilgwa (各色熟實果) was used and a mixture of "Imin-Jinyeoneuigwe (壬寅進宴儀軌)" (November 1902) included the assorted-sulsilgwa (各色熟實果).