• Title/Summary/Keyword: Diffuse Field

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Two Cases of Bilateral Diffuse Cystic Lesion (양측성 미만성 소낭포성 병변 2예)

  • Lim, Dong-Jun;Lee, So-Young;Hong, Chang-Kyun;Song, So-Hyang;Kim, Chi-Hong;Moon, Hwa-Sik;Song, Jeong-Sup;Park, Sung-Hak
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.2
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    • pp.246-252
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    • 2000
  • Lymphangioleiomyomatosis(LAM) is a rare disease of unknown etiology that occurs mainly in woman in her reproductive age. We recently experienced two cases of bilateral diffuse cystic lesion of the lung on chest X-ray and HRCT. The first case, a 26-year-old female, who had been diagnosed with tuberous sclerosis by the presence of clinical manifestation such as mental retardation, bilateral renal angiomyolipoma, adenoma sebaceum and generalized seizure, was admitted due to a recently developed hemoptysis. Chest PA showed diffuse ground-glass opacity with radiolucent cystic lesions of various sizes on both lung fields. HRCT showed innumerable small cystic lesions with suspicious diffuse ground-glass opacity on both lung fields The second case, a 30-year-old fema1e was admitted due to dyspnea and spewing of blood-tinged sputum for 2 weeks, shortly after delivery. Chest PA showed diffuse reticular and ground-glass opacities on both lung field. HRCT showed multiple well-defined and relatively uniform size air cysts with a uniform wall thickness on entire both lung fields, with small amount of right pleural effusion. By thoracoscopic lung biopsy she was diagnosed with pulmonary lymphangioleiomyomatosis. We report these cases with a brief review of the literatures.

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PHYSICAL CONDITIONS IN DARK INTERSTELLAR CLOUDS: MAGNETIC FIELD STRENGTH AND DENSITY

  • Hong, S.S.
    • Journal of The Korean Astronomical Society
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    • v.14 no.1
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    • pp.37-42
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    • 1981
  • In order to know how the magnetic field increases with density in interstellar clouds, we have analyzed observations of extinction and polarization for stars in the ${\rho}$ Oph molecular cloud complex. The size of grains in dense parts of the complex is estimated to be larger than the ones in diffuse interstellar clouds by about 15 percent in radii. Employing the Davis-Greenstein mechanism for grain alignment with this estimated grain size, we have put constraints on the exponent in the field-density relation $B{\propto}n^x:1/5{\leq}x{\leq}1/3$. It is concluded that magnetic field in gravitationally contracting clouds increases less steeply than the classical expectation based on the approximation of isotropic contraction with complete frozen-in flux.

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Analysis of axial magnetic field of coil type vacuum interrupter electrodes by comparing effective area at mid-gap plane (유효면적비교를 통한 COIL TYPE 진공인터럽터 전극의 측자계 분석)

  • Kim, Byoung-Chul;Yoon, Jae-Hun;Hoe, Jun;Kang, Seong-Wha;Lim, Kee-Joe
    • Proceedings of the KIEE Conference
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    • 2008.05a
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    • pp.147-148
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    • 2008
  • In this paper, we calculated the axial magnetic field at mid-gap plane between upper and lower electrode in vacuum interrupter by means of commercial finite element method Maxwell 3D and compared on the basis of "effective area" criterion. The models used in this paper are coil type(axial magnetic field) vacuum interrupter electrodes which have different numbers of coil segment. We used Dr. Schulmann's experimental equation which indicates minimum critical value of axial magnetic field to diffuse arc.

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Reconsideration on the Diffsuse Sound Field (확산음장에 관한 고찰)

  • 강현주
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1998.06c
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    • pp.331.2-336
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    • 1998
  • In this paper, the validity for the application of the diffuse sound field theoty to the real sound field, especially on the bounding surfaces of the rooms, was reconsidered. The analytical result for directivity pattern on the bounding surfaces of the room was compared with the result of numerical simulations using ray tracing technique. Comparison results show that the distribution of the incident sound energy vs incident angles is approximated to Gaussian distribution, not to the uniform distribution.

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The Technical Trend and Prospect of Ozonizer (오존발생기의 기술동향 및 전망)

  • Cho, Kook-Hee;Kim, Young-Bae;Lee, Hyeong-Ho
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1655-1657
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    • 2001
  • Ozone is widely used to sterilize food and tap water because ozone is a strong oxidizer. Efficient ozone generation is the most important issue in the field of ozone application. A variable discharge type of ozonizer that generates diffuse glow discharge in air at atmospheric pressure was used for the efficient ozone generation.

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POLARIZATION OBSERVATIONS OF RADIO SOURCES IN THE FIELD CONTAINING ABELL 695

  • Kim, Kwang-Tae
    • Journal of The Korean Astronomical Society
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    • v.21 no.2
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    • pp.117-132
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    • 1988
  • Multi-frequency polarization observations of Abell 695 are reported here. The brightest radio source 0838+325, which was previously classified as a wide angled head-tail radio source, is, in the present observations, resolved into two separable sources, a head-tail source 0838+325 AB and a diffuse one 0838+325C. The radio-tail shows high degree of linear polarization(${\sim}50$-25%) along the radio-tail, suggesting that the interaction with its surrounding intracluster medium (ICM) is not highly turbulent. With the present data, thermal particle densities at the locations of these sources are estimated to be n > $10^{-5}\;cm^{-3}$.

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Experimental evaluation of sound Insulation performance of ceiling panels (천장재 차음성능의 실험 평가)

  • 강현주;김상렬;김재승;김현실;김봉기
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.05a
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    • pp.1067-1070
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    • 2002
  • This paper deals with the factors affecting measurement of sound insulation performance of the ceiling panels. The factors to be experimently examined are as follows: sound diffuseness of the test room by investigating sound pressure distribution, Reverberation time, and influence of speaker location on measured results. Based on the investigation of sound pressure distribution over measuring points, it can draw a conclusion that rectangular shaped rooms as test rooms have a serious problem associated with the diffuse sound field.

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Sound Energy Distributions according to Incident Angles on the Bounding Surfaces in the Reverberation Room (잔향실 경계면에서 입사각에 따른 음에너지 분포)

  • 강현주;이정권;김현실;김재승;김상렬
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.10a
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    • pp.279-285
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    • 1997
  • In this paper, the validity for the application of the diffuse sound field theory to the real sound filed, especially on the bounding surfaces of the rooms, was studied. Numerical simulations using ray tracing technique for two models, namely spheres and a reverberant room, were performed. Calculation results show that the distribution of the incident sound energy vs incident angles is approximated to Gaussian distribution, not to the uniform distribution.

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A Study on Estimating Diffuse Pollution Loads Removal by Road Vacuum Cleaning (도로청소에 의한 비점오염부하 삭감량 산정방법 연구)

  • Lee, Taehwan;Cho, Hong-Lae;Jeong, Euisang;Koo, Bhon K.;Park, Baekyung;Kim, Yongseok
    • Journal of Korean Society on Water Environment
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    • v.33 no.2
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    • pp.123-129
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    • 2017
  • The purpose of this study is to identify potential methodologies to reasonably estimate the effectiveness of road vacuum cleaning in terms of pollution loads reduction. In this context, this study proposes two empirical equations to estimate the amount of diffuse pollution loads removed by road vacuum cleaning. The proposed equations estimate the removed amount of pollution loads respectively taking into consideration of: a) the distance of road vacuum cleaning; and b) the amount of road-deposited sediment(RDS). All of the parameters in these equations were evaluated based on results of field monitoring and laboratory analyses, except for the RDS generation rate. The results of this study suggest that pollutant removal efficiency is 46.3% for $BOD_5$ and 56.4% for TP; discharge ratios for particulate and dissolved $BOD_5$ are 35.0% and 21.2%, respectively; discharge ratios for particulate and dissolved TP are 35.0% and 19.4%, respectively. Average concentrations of pollutants in RDS are $BOD_5$ 977.3 mg/kg and TP 317.6 mg/kg. Some results of a case study imply that both equations can be potentially useful if the adopted parameters are reasonably evaluated. In particular, the RDS generation rate should be evaluated based on monitoring data collected from various road conditions.

Histopathological classification of the bovine lymphoma caused by bovine leukemia virus in Korea (소 백혈병 바이러스 감염에 의한 소 림프종의 병리조직학적 분류)

  • Yoon, Soon-Seek;Lee, Kyeong-Hyun;Bae, You-Chan;Jean, Young-Hwa;Kang, Mun-Il;Lee, O-Soo;Han, Hong-Ryul
    • Korean Journal of Veterinary Research
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    • v.45 no.3
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    • pp.391-398
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    • 2005
  • Several studies have been performed on the bovine leukemia since bovine leukemia virus (BLV) had been detected in 1982 in Korea. We have conducted histopathological study on the bovine lymphoma caused by BLV because only limited results were reported on the pathological characterization of lymphoma. Lymphoma tissues were obtained from cattle necropsied and slaughtered during a designated period. Lymphoma was classified histopathologically according to the National Cancer Institute Working Formulation. Leukotic tissues consisted of fairly uniform sheets of closely packed medium to large lymphocytes without any architectural arrangement in all 30 cases. Twenty five cases belong to diffuse large cell type, while three cases were diffuse mixed cell type, and two cases were immunoblastic large cell type among 30 cases. Follicular type lymphoma was not detected in this study. The mitotic index of tumor cells showed average 2.5 in the field of 400X. Nuclear cleavage was detected in 53% of cases. Multi-nucleated cells were detected among tumor cells in 30% of lymphoma cases. In conclusion, the most common morphologic cell type of bovine lymphoma in Korea was a diffuse large cell type with multinucleated cells and nuclear cleavages.