• Title/Summary/Keyword: Edge preservation

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A Study on Hybrid Filter Algorithm for Image Denoising (영상 잡음제거를 위한 하이브리드 필터 알고리즘에 관한 연구)

  • Yinyu, Gao;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2012.05a
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    • pp.127-129
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    • 2012
  • Due to the prevalence of digital camera, multi-media etc. the image is being used in everyday life. However, noise always damages the image and the image denoising technology is important part for improving the image visual quality. There are many existing methods to remove noise such as wiener filter, mean filter and VisuShrink etc. However, they perform not good enough for denoising. Hence, in this paper we proposed a hybrid filter algorithm which consists of wiener filter and modified wavelet based thresholding method using adaptive threshold and thresholding function. The proposed algorithm shows not only better low frequency and high frequency property, but also the outstanding noise suppression and edge preservation properties.

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Reconstruction of Magnetic Resonance Phase Images using the Compressed Sensing Technique (압축 센싱 기법을 이용한 MRI 위상 영상의 재구성)

  • Lee, J.E.;Cho, M.H.;Lee, S.Y.
    • Journal of Biomedical Engineering Research
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    • v.31 no.6
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    • pp.464-471
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    • 2010
  • Compressed sensing can be used to reduce scan time or to enhance spatial resolution in MRI. It is now recognized that compressed sensing works well in reconstructing magnitude images if the sampling mask and the sparsifying transform are well chosen. Phase images also play important roles in MRI particularly in chemical shift imaging and magnetic resonance electrical impedance tomography (MREIT). We reconstruct MRI phase images using the compressed sensing technique. Through computer simulation and real MRI experiments, we reconstructed phase images using the compressed sensing technique and we compared them with the ones reconstructed by conventional Fourier reconstruction technique. As compared to conventional Fourier reconstruction with the same number of phase encoding steps, compressed sensing shows better performance in terms of mean squared phase error and edge preservation. We expect compressed sensing can be used to reduce the scan time or to enhance spatial resolution of MREIT.

Choosing a culture medium for SCNT and iSCNT reconstructed embryos: from domestic to wildlife species

  • Cordova, A.;King, W.A.;Mastromonaco, G.F.
    • Journal of Animal Science and Technology
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    • v.59 no.11
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    • pp.24.1-24.14
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    • 2017
  • Over the past decades, in vitro culture media have been developed to successfully support IVF embryo growth in a variety of species. Advanced reproductive technologies, such as somatic cell nuclear transfer (SCNT), challenge us with a new type of embryo, with special nutritional requirements and altered physiology under in vitro conditions. Numerous studies have successfully reconstructed cloned embryos of domestic animals for biomedical research and livestock production. However, studies evaluating suitable culture conditions for SCNT embryos in wildlife species are scarce (for both intra- and interspecies SCNT). Most of the existing studies derive from previous IVF work done in conventional domestic species. Extrapolation to non-domestic species presents significant challenges since we lack information on reproductive processes and embryo development in most wildlife species. Given the challenges in adapting culture media and conditions from IVF to SCNT embryos, developmental competence of SCNT embryos remains low. This review summarizes research efforts to tailor culture media to SCNT embryos and explore the different outcomes in diverse species. It will also consider how these culture media protocols have been extrapolated to wildlife species, most particularly using SCNT as a cutting-edge technical resource to assist in the preservation of endangered species.

Quantitative Evaluation of Sparse-view CT Images Obtained with Iterative Image Reconstruction Methods (반복적 연산으로 얻은 Sparse-view CT 영상에 대한 정량적 평가)

  • Kim, H.S.;Gao, Jie;Cho, M.H.;Lee, S.Y.
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.257-263
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    • 2011
  • Sparse-view CT imaging is considered to be a solution to reduce x-ray dose of CT. Sparse-view CT imaging may have severe streak artifacts that could compromise the image qualities. We have compared quality of sparseview images reconstructed with two representative iterative reconstruction techniques, SIRT and TV-minimization, in terms of image error and edge preservation. In the comparison study, we have used the Shepp-Logan phantom image and real CT images obtained with a micro-CT. In both phantom image and real CT image tests, TV-minimization technique shows the best performance in error reduction and preserving edges. However, the excessive computation time of TV-minimization is a technical challenge for the practical use.

A Study on Removal of Salt and Pepper Noise using Deformable Masks Depending on the Noise Density (잡음 밀도에 따라 가변 마스크를 적용한 Salt and Pepper 잡음 제거에 관한 연구)

  • Hong, Sang-Woo;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.9
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    • pp.2173-2179
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    • 2015
  • In digital era image processing has been utilized in a variety of media such as TV, camera and smart phone. Typically salt and pepper noise are generated by various causes during the analysis, identification, and processing of image data. Principal filters such as SMF, CWMF, and AMF have been used to remove these noise. But the existing filters fall short of edge preservation and noise elimination in high noise densities. Thus, a processing algorithm, on which the size of deformable mask varies depending on the noise density, is proposed to remove salt and pepper noise effectively in this study. The performance of the proposed method was evaluated compared with the existing methods using PSNR.

Image Reduction Filter for Edge Preservation in Salt and Pepper Noise Environments (Salt and Pepper 잡음 환경에서 에지 보존을 위한 영상 복원 필터)

  • Kwon, Se-Ik;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.953-955
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    • 2016
  • Degradation is occurred in the process of the signal transmission in the image processing system due to various reasons. Degradation is noise addition in the image signal and the representative one to cause degradation is salt and pepper noise. Therefore, image restoring filter was suggested in this article to apply and process weighted value by the changes of each directional pixel upon breakdown of local mask with 8 directions in order to restore the damaged image in the environment of salt and pepper noise. In addition, peak signal to noise ratio (PSNR) was used to compare the existing method as the objective determinant standard of the improvement effect.

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Nanotechnology in reproductive medicine: Opportunities for clinical translation

  • Shandilya, Ruchita;Pathak, Neelam;Lohiya, Nirmal Kumar;Sharma, Radhey Shyam;Mishra, Pradyumna Kumar
    • Clinical and Experimental Reproductive Medicine
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    • v.47 no.4
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    • pp.245-262
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    • 2020
  • In recent years, nanotechnology has revolutionized global healthcare and has been predicted to exert a remarkable effect on clinical medicine. In this context, the clinical use of nanomaterials for cancer diagnosis, fertility preservation, and the management of infertility and other pathologies linked to pubertal development, menopause, sexually transmitted infections, and HIV (human immunodeficiency virus) has substantial promise to fill the existing lacunae in reproductive healthcare. Of late, a number of clinical trials involving the use of nanoparticles for the early detection of reproductive tract infections and cancers, targeted drug delivery, and cellular therapeutics have been conducted. However, most of these trials of nanoengineering are still at a nascent stage, and better synergy between pharmaceutics, chemistry, and cutting-edge molecular sciences is needed for effective translation of these interventions from bench to bedside. To bridge the gap between translational outcome and product development, strategic partnerships with the insight and ability to anticipate challenges, as well as an indepth understanding of the molecular pathways involved, are highly essential. Such amalgamations would overcome the regulatory gauntlet and technical hurdles, thereby facilitating the effective clinical translation of these nano-based tools and technologies. The present review comprehensively focuses on emerging applications of nanotechnology, which holds enormous promise for improved therapeutics and early diagnosis of various human reproductive tract diseases and conditions.

Rearrangement of the Designated Area and Modification of Features of Buryeongsa Valley as a Scenic Site (불영사계곡의 명승 지정구역 조정 및 현상변경 방안 연구)

  • Ahn, Seung-Hong;Hong, Youn-Soon;Kim, Hak-Beom
    • Journal of the Korean Institute of Landscape Architecture
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    • v.37 no.6
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    • pp.48-56
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    • 2010
  • Since ancient times, Korea has been called a land of beauty. Scenic sites under the Cultural Properties Protection Act include picturesque places that are famous for their natural scenic beauty as well as their historical and cultural value. Scenic sites are managed as natural assets to promote their preservation and use. However, the management of scenic sites can produce adverse effects on regional development and ownership rights. Moreover, the purpose of their designation as cultural assets is not fully understood because scenic sites are managed by focusing on restraint on users' act the same as was applied to historic sites. Therefore, the purpose of this study is to protect inhabitants' rights of ownership by arranging the boundaries of designated areas and by providing standard permission for condition changes in the Buryeongsa Valley, which was designated as a Scenic Site in 1979. The results of this study can be summarized as follows: First, arranging the boundaries of the designated area includes the arrangement of the edge lines standardized on the visual range of the mountain ridge, preventing the loss of landscape beauty in the designated district; the internal clearing district focuses on the existing settlement. Gearing the designated areas after the arrangement of the boundaries results in $11,928,932m^2$, 38.6% compared to the existing designated areas. Second, it establishes a 500m buffer zone inside the radius of the boundary of the cultural asset as a standard for condition changes that seriously affect landscape preservation. Third, the standards for permission on building 'height regulations' are divided into flat and gable, according to the roof shape. The adopted standard is 8m high for 2 story flat roofs, and 12m high for 2 story gable roofs.

2D Industrial Image Registration Method for the Detection of Defects (결함 검출을 위한 2차원 산업 영상 정합 기법)

  • Lee, Youngjoo;Lee, Jeongjin
    • Journal of Korea Multimedia Society
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    • v.15 no.11
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    • pp.1369-1376
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    • 2012
  • In this paper, we propose 2D industrial image registration method for the detection of defects. Proposed method performs preprocessing to smooth the original image with the preservation of the edge for the robust registration against general noise. Then, x-direction gradient magnitude image and corresponding binary image are generated. Density analysis around neighborhood regions per pixel are performed to generate feature image for preventing mis-registration due to moire-like patterns, which frequently happen in industrial images. Finally, 2D image registration based on phase correlation between feature images is performed to calculate translational parameters to align two images rapidly and optimally. Experimental results showed that the registration accuracy of proposed method for the real industrial images was 100% and our method was about twenty times faster than the previous method. Our fast and accurate method could be used for the real industrial applications.

Removal of Submandibular Stones via Intraoral approach (구강내 접근을 이용한 악하선 타석의 제거)

  • Lee, Sung-Bu;Lee, Jong-Cheol;Choi, Seung-Ho;Kim, Sang-Yoon;Nam, Soon-Yuhl
    • Korean Journal of Bronchoesophagology
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    • v.14 no.1
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    • pp.23-28
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    • 2008
  • Background and Objectives : Traditionally, the excision of submandibular gland (SMG) has been commonly used for treatment of calculi in the proximal duct or gland parenchyma. Over the last 10 years several new minimally invasive techniques including lithotripsy, sialendoscope were introduced in the treatment of sialolithiasis. But these have some limitation on large, infected calculi. The aim of this study is to assess the intraoral treatment of submadibular stones. Subjects and Method : The records of one hundred and seventy-three patients who underwent intraoral removal of submadibular sialolithiasis between June 1, 1989 and July 31, 2006 were retrospectively reviewed. Results : Stone location was distal to the edge of the mylohyoid muscle in 127 patients and proximal to gland in 48 patients (mean size of sialoliths, 7.1mm [range 3.0-25mm]). The complete removal of stones was observed in 170 (97.1%) patients regardless of size and location. Recurrence of lithiasis was found in 8 patients (then treated with intraoral removal in 5 patientsand resection of SMG (submandibular glands) in 3 patients). Acalculous sialadenitis in 9 patients (5.1%) and cyst formation in 2 patients (1.1%) was found. But no evidence of postoperative complications including hemorrhage, fistula, damage to lingual nerve were found. Conclusion : The intraoral removal of submandibular stone is useful in preservation of submandiblar function and effective in palpable stones regardless of location, size.

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