• Earthquakes and Structures
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• v.3 no.3_4
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• pp.507-518
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• 2012

It is now widely accepted that the resulting displacement field within elastic, inhomogeneous, anisotropic solids subjected to equipartitioned, uniform illumination from uncorrelated sources, has intensities that follow diffusion-like equations. Typically, coda waves are invoked to illustrate this concept. These waves arrive later as a consequence of multiple scattering and appear at "the tail" (coda, in Latin) of seismograms and are usually considered an example of diffuse field. It has been demonstrated that the average correlations of motions within a diffuse field, in frequency domain, is proportional to the imaginary part of Green's function tensor. If only one station is available, the average autocorrelation is equal to the average squared amplitudes or the average power spectrum and this gives the Green's function at the source itself. Several works address this point from theoretical and experimental point of view. However, a complete and explicit analytical description is lacking. In this work we study analytically some properties of the Green's function, specifically the imaginary part of Green's function for 2D antiplane problems. This choice is guided by the fact that these scalar problems have a closed analytical solution (Kausel 2006). We assume the diffusiveness of the field and explore its analytical consequences.

• Tuberculosis and Respiratory Diseases
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• v.56 no.6
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• pp.683-686
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• 2004

Pulmonary alveolar proteinosis is a rare disorder in which lipoproteinaceous material accumulates within the alveoli. We report a case of pulmonary alveolar proteinosis in a 41 year old female patient. She complained of a dry cough in the preceding 6 months. She presented symptoms of mild hypoxemia and diffuse infiltration at both lower lung fields. A milky fluid was obtained by bronchoalveolar lavage. We confirmed by light microscopic examinations of the lung tissues obtained by transbronchial lung biopsy. Through several follow-ups, the patients symptoms were mild.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.7
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• pp.1633-1641
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• 1996

In this paper we propose a new method for anlayzing the properties of surface reflectance and reconstructing the shape of object using estimated reflectance parameters. We have investigated the hybrid reflectance surface which has specularreflection and diffuse reflection, which can be explained by Torrance-Sparrow model. Sample sphere made on one maerial is used to estimate the reflectance properties by using LMS algorithm. We can make the reference image which consists of surface normal and brightness value using estimated reflectance parameters, and thenarbitrary shape object made of the same material as sample can be reconstructed by matching with reference image. Photometric matching method proposed in this paper is robust because it mateches object image with the reference imageconsidering its neighbor brightness distribution. Also, in this paper plate diffuse illumination is used to remove intensity disparity with simple scheme. It is expected that the proposed algorithm can be applied to 3D recognition, vision inspection system and other fields.

• Journal of Digital Convergence
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• v.13 no.9
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• pp.489-495
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• 2015

Image availability evaluated by the degree of agreement and sensitive using the process improve visualization according to the Algorithm modification in Image Post-Processing. Reliability measured by the Breast Imaging Reporting and Data System. 172 patients visit same period divided by BI-RADS, category five stages, and contents of breast parenchyma into Calcification, Nodule and Mass. Evaluated the TE/PV image reliability, visualization sensitive, agreement of diagnosis. Convergence analysis was an in various fields. According to the result of this research, PV has higher sensitive and accuracy about lesions than TE visual and there is a difference insensitive by contents of breast parenchyma. Therefore, practical use of Algorithm Modification(Tissue Equalization: TE, Premium View: PV) is expected to improve more accurate, useful diagnosis, which has not been easy until now.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.473-480
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• 1997

This paper presents the feasibility of the assumption that incident sound to panels might have a Gaussian distribution, instead of the well-known uniform distribution in the analysis of sound transmission loss of panels. Being compared with the latter, it seems that the former is physically more concrete. To prove the assumption, the problems with diffuse fields in reverberation room are considered by case study and comparisions of the prediction with the measurement of sound transmission loss of walls are performed. The results show good agreement between the two values.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.36.1-36.1
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• 2021

Galaxy clusters host Mpc-scale diffuse radio emission giving us evidence of large-scale magnetic fields in the Universe. It is relevant to understand magnetic field amplification processes occurring at the center and outskirts of galaxy clusters. Each of these processes are believed to give rise to observed radio haloes and radio relics, respectively. In this work, we focus on studying the continuum and polarised emission in radio relics. We use threedimensional magnetohydrodynamical simulations of merger shock waves propagating through a magnetized, turbulent intracluster medium. Our model includes the diffusive shock acceleration (DSA) of cosmic ray electrons, their spatial advection and energy losses at run-time. We discuss the relation between the mock observation features and the underlying morphology of the magnetic field.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1376-1378
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• 2006

Numerical and experimental study were carried out to characterize sound fields of low frequency in a scaled reverberation chamber for measurement of sound insulation of panels. By using BEM, lower modes of the chamber are identified and then predicted the effect of diffusers in order to destruct lower modes. Compared results with measurements show reasonable agreements, especially at the first end second modes. Based on numerical prediction, the diffuser are installed in order to improve sound fields to be more diffuse than ever. It is found that the diffuser put in nodal line of the chamber destruct evidently the first mode. Consequently, the measuring error at the low frequency can be relatively reduced compare to the case of without diffuser.

• Tuberculosis and Respiratory Diseases
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• v.40 no.1
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• pp.79-83
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• 1993

A 38-year-old female was admitted due to progressive exertional dyspnea and intermittent blood tinged sputum. Chest PA showed diffuse reticular infiltration accompanied by hyperinflation. $PaO_2$ was normal in resting state but profoundly decreased during exercise. Spirometry showed severe obstructive pattern but DLCO was markedly decreased. Lung volumes measured by helium equilibrium method was increased. On HRCT, numerous and relatively uniform sized cysts were evenly distributed throughout the bilateral lung fields. Open lung biopsy was performed and pulmonary lymphangioleiomyomatosis(LAM) was diagnosed based on the findings of abnormal proliferation of smooth muscle cells in the walls of lymphatic vessels, bronchioles, and small pulmonary veins. Immunohistochemical staining was negative for estrogen receptor but positive for progesterone receptor. Medroxyprogesterone therapy was initiated.

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.285-290
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• 1996

Diffuse panbronchiolitis is a chronic inflammatory lung disease of unknown etiology which is characterized by chronic airflow limitation and airway inflammation, predominantly localized in the respiratory bronchioles with infiltration of inflammatory cells, and has typical clinical, radiological and pathological features. Obstructive respiratory functional impairment, occasional symptoms of wheezing, and also cough and sputum resemble the feature of emphysema, bronchial asthma, or chronic bronchitis, respectively. We experienced a case of pathologically proven advanced diffuse panbronchiolitis in a 55-year-old man with productive cough and exertional dyspnea. The chest radiography showed multiple tiny nodular densities on whole lung fields. It was confirmed by thoracoscopy-guided lung biopsy and the patient was improved after initiation of treatment with low-dose erythromycin.

• Tuberculosis and Respiratory Diseases
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• v.61 no.3
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• pp.294-298
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• 2006

Lymphocytic interstitial pneumonia(LIP) is an uncommon condition in which the alveolar septa and extra-alveolar interstitial space are markedly expanded by small lymphocytes, plasma cells and histiocytes. Chest radiographs generally show nonspecific patterns with the most common pattern showing bibasilar reticular or reticulonodular infiltrates. Hilar or mediastinal lymphadenopathy and pleural effusions are usually absent. We encountered a 42-year-old female patient who was admitted to hospital because of exertional dyspnea and palpitation. The chest X-ray showed an enlarged bilateral hilar shadow and diffusely increased bronchovascular markings in both lung fields. The chest CT showed diffuse nodular infiltrations with mild septal thickening and combined patchy ground glass opacity in both lungs, and conglomerated mediastinal and bilateral hilar lymphadenopathy. A diagnosis of LIP was made from the tissue pathology taken by a thoracoscopic lung biopsy. The patient showed clinical and radiographic improvement after 3 months of treatment with prednisolone. We report a case of LIP presenting as diffuse nodular interstitial infiltrations with multiple mediastinal and bilateral hilar lymphadenopathy.