• Title/Summary/Keyword: Patch Distribution

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A Case of Bronchiolitis Obliterans Organizing Pneumonia Associated with Wheezing (천식음이 동반된 Bronchiolitis Obliterans Organizing Pneumonia 1예)

  • Lee, Jae-Seok;Kim, Do-Jin;Ahn, Young-Soo;Lee, Sang-Moo;Kim, Hyeon-Tae;Uh, Soo-Taek;Kim, Yong-Hoon;Park, Choon-Sik
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.6
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    • pp.730-735
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    • 1993
  • BOOP is a clinopathologic entity consisting of a flu-like illness, late inspiratory crackles, and pathologically granulation tissue plugs within lumens of small airways sometimes with complete obstruction of small airways and granulation tissue extending into alveolar ducts and alveoli with a variable degree of interstitial infiltration of mononuclear cells and accumulation of foamy macrophages in alveolar spaces in a patch distribution, and preservation of background architecture of the lung. It has patch infiltrates roentgenographically, and restrictive ventilatory defect pysiologically such as decreased vital capacity. and diffusing capacity. The BOOP has been observed in the context of collagen vascular disease, and other autoimmune disease secondary to treatment with penicillamine, bleomycin, acebutolol and amiodarone, following the inhalation of toxic fumes, after several infections including measles, pertussis and influenza and idiopathic. Clinically, response to coricosteroid therapy is good and relapse dose not occur if sufficient theraphy is good. A flu-like illness occurs in one third, cough in one third, cough with dyspnea in the remaining patients. Hemoptysis are rare. The physical examination reveales dry crackles in the majority of the patients with BOOP but rarely associated with wheezing. The duration of illness is less than 2 months in 75% of patients. With a brief review of literature, we report a case of the BOOP which is good response to steroid, but frequent relapse and assoicated with wheezing.

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Simulation of Low-Grazing-Angle Coherent Sea Clutter (Low Grazing Angle에서의 코히어런트 해상 클러터 시뮬레이션)

  • Choi, Sang-Hyun;Song, Ji-Min;Jeon, Hyeon-Mu;Chung, Yong-Seek;Kim, Jong-Mann;Hong, Seong-Won;Yang, Hoon-Gee
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.29 no.8
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    • pp.615-623
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    • 2018
  • The probability density function(PDF) for the amplitude of the reflectivity of low-grazing-angle sea clutter has generally been modeled by a compound-Gaussian distribution, rather than by the Rayleigh distribution, owing to the intensity variation of each clutter patch over time. The texture component forming the reflectivity has been simulated by combining Gamma distribution and memory-less nonlinear transformation(MNLT). On the other hand, there is no typical method available that can be used to simulate the speckle component. We first review Watt's method, wherein the speckle is simulated starting from the Doppler spectrum of the received echoes that is modeled as having a Gaussian shape. Then, we introduce a newly proposed method. The proposed method simulates the speckle by manipulating a clutter covariance matrix through the Cholesky decomposition after minimizing the effect of adjacent clutter patches using an equalizer. The feasibility of the proposed method is validated through simulation, wherein the results from two methods are compared in terms of the Doppler spectrum and the correlation function.

Spatial Distribution Pattern of Patches of Erythronium japonicum at Mt. Geumjeong in Korea (한국 금정산에 븐포하고 있는 얼레지의 공간적 분포 양상과 집단 구조)

  • Man Kyu Huh
    • Journal of Life Science
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    • v.33 no.3
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    • pp.227-233
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    • 2023
  • The purpose of this paper was to describe a statistical analysis for the spatial distribution of geographical distances of Erythronium japonicum at Mt. Geumjeong in Korea. The spatial pattern of E. japonicum was analyzed according to the nearest neighbor rule, population aggregation under different plot sizes by dispersion indices, and spatial autocorrelation. Most natural plots of E. japonicum were uniformly distributed in the forest community. Disturbed plots were aggregately distributed within 5 m × 5 m of one another. Neighboring patches of E. japonicum were predominantly 7.5~10 m apart on average. If the natural populations of E. japonicum were disturbed by human activities, then the aggregation occurred in a shorter distance than the 7.5~10 m distance scale. The Morisita index (IM) is related to the patchiness index (PAI) that showed the 2.5 m × 5 m plot had an overly steep slope at the west and south areas when the area was smaller than 5 m × 5 m. When the patch size was one 2.5 m × 5 m quadrat at the west distributed area of Mt. Geumjeong, the cluster was determined by both species characteristics and environmental factors. The comparison of Moran's I values to a logistic regression indicated that individuals in E. japonicum populations at Mt. Geumjeong could be explained by isolation by distance.

Development of an Approach for Analysing Vegetation Community Mosaic Using Landscape Metrics (경관지수를 활용한 식생군락 모자이크화 분석법)

  • Lee, Peter Sang-Hoon;Jeong, Jong-Chul
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.161-178
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    • 2017
  • Whereas the demand for development of forested areas covering more than 60% of Korean territory, permission on the forest development has been still given from the perspective of effective land utilization rather than conservation. As the assessment of large forested areas usually focuses more on forest structure, it has its limitation of observing and analyzing the interior change in forest in this way. This study was aimed at computing landscape metrics using a presence vegetation map and FRAGTSTATS 4.2 and analyzing vegetation mosaics. Colonies in native vegetation were classified into a series of major groups and sub-groups based on the native species within the colonies. The colonies were investigated by analyzing a suite of landscape metrics - Core Area, Percentage of Landscape, Number of Patches, Patch Density, Largest Patch Index, Total Edge, Edge Density, Landscape Shape Index, Mean Patch Area, Euclidean Nearest Neighbor. In the Chungnam province major groups and sub-groups of colonies classified based on the proportion of pine and oak species, and pine species was the principal one in terms of distribution area. As for the competition between pines and oaks, while the coverage of pine-centered colonies were three times larger than those of oak-centered ones, pine colonies showed the greater number of patches and therefore higher fragmentation than oaks at the major group level. For the sub-groups, the largest coverage colonies were not only indicated by Pinus densiflora-Quesrcus mongolica colonies among P. densiflora-centered colonies, Q. accutissima colonies among Q. accutissima-centered ones, Q. accutissima-P. densiflora colonies among Q. accutissima-centered ones, Q. mongolica colonies among Q. mongolica-centered ones, P. thumbergii colonies among P. thumbergii-centered ones, and Q. serrata-Q. acutissima colonies among Q. serrata-centered ones, but also revealed more severely mosaicked than other smaller colonies. The overall mosaicking degree estimated by landscape metrics was considered useful for monitoring and investigating vegetation. However, in order to develop management strategy based on analyzing the reason for the mosaicking process and anticipating a trend in vegetation succession, it is essential to further study about ecological characteristics of each colony in the vegetation.

A Study on Near-Field to Far-Field Transformation Using Stratton-Chu Formula (Stratton-Chu 공식을 이용한 측정된 근거리장에서 원거리장으로의 변환에 관한 연구)

  • Lee, Jeong-Seok;Song, Tae-Lim;Du, Jin-Kyoung;Koo, Tae-Wan;Yook, Jong-Gwan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.3
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    • pp.316-323
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    • 2013
  • This paper deals with the near-field to far-field calculation for far-field characteristics of antenna and electromagnetic compatibility(EMC) testing. Since the conventional EMC testing process is inefficient such as measurements of the wide band signals and mega structures, Stratton-Chu formula is used to predict the far-field emission by simple and direct process. The usefulness of Stratton-Chu formula is verified by comparing to the analytic solution of the uniform distribution aperture in free-space. In order to inspect the far-fields and to get the near-field values, full-wave simulation solver is utilized. Through the full-wave simulation about the patch antenna, calculated far-field results from Stratton-Chu formula are proven. The predicted magnitudes of the far-field are in error by less than 6 %.

Dual-band reconfigurable monopole antenna using a PIN diode (PIN 다이오드를 이용한 WLAN용 재구성 모노폴 안테나)

  • Mun, Seung-Min;Yoong, Joong-Han;Kim, Gi-Re
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.9
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    • pp.1633-1640
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    • 2016
  • In this paper, we propose a open-ended rectangular microstirp patch antenna with fork-shaped feeding structure. This antenna extends the effective bandwidth by transforming single or multi resonant frequency and is designed planar monopole structure with microstrip line to satisfy the WLAN bands (2.4 - 2.484, 5.15 - 5.35, 5.25-5.825 GHz). The substrate is printed in 0.8 mm thickness on an FR-4 board. A commercial 3D simulation tool was used to analyze surface current and electromagnetic field distribution in order to analyze the operation mode and reconfiguration principle of antenna. According to the lengths of individual patches, simulated reflection loss was compared to obtain optimized values. When it was designed with the optimized values, it satisfied WLAN bands (2.380 - 2.710, 4.900 - 5.950 GHz), if the switch is off, and 2.4 WLAN band (2.380 - 2.710 GHz). From the fabricated and measured results, measured results of return loss, gain and radiation patterns characteristics displayed for operating bands.

A Study on the Biotope's Characters of the Mixed Rural City(II) - The Analysis of Change in Land Uses and Forest Structure of Sunghwan in Chonan City using Remote Sensing - (도농통합형 도시에 있어서 생물서식처 공간특성에 관한 연구(II) - 천안시 성환읍의 토지이용변화추이와 녹지구조변화를 중심으로 -)

  • Lee, Jin-Hee;Bang, Kwang-Ja;Kim, Hoon-Hee
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.2 no.1
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    • pp.38-47
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    • 1999
  • The mixed rural city is adjusting to change by urbanization. The recent landcover change in mixed rural city is an important factor that changes structure and function of regional ecosystem. Landscape ecology is an integrated ecology widely available for environmental science such as nature conservation and sustainable land-use planning. As the concern about environmental quality rises, many studies are trying to create and conservate for biotop. The creation of biotop is related to the plan and management of the effective landuse because the important factor to change the structure and function of ecological area in the country. This study was carried out to establish the foundation of the landuse plan to analyze the change of landuse and to plan the scheme in creating biotop and landuse. We used the approach of ecological landscape and using landscape indices with RS(Remote Sensing) and GIS(Geographic Information System) technology, spatio-temporal variations of areas and distribution of forest patches were examined in the Sunghwan in Chonan from 1985 to 1996. A result of this study showed that the area of forest and paddy decreased by urban sprawl. The size of patch in the forest and agriculture had been smaller and irregular form, heterogeneity of size of forest and agriculture patches within sub-basin was increased, pattern of forest and agriculture patches decreased the corridor and network from 1985 to 1996.

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The Records of Origin and Transport of Sediments From the Past to the Present in the Yellow Sea

  • Yi, Hi-Il;Chun, Jong-Hwa;Shin, Im-C.;Shin, Dong-Hyeok;Jou, Hyeong-Tae
    • Journal of the korean society of oceanography
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    • v.39 no.1
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    • pp.96-106
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    • 2004
  • A total of 116 surface sediment samples were obtained on the Yellow Sea and analyzed for grain size and geochemical elements in order to interpret the present sediment transportation. Thirty-nine cores and 3,070 line-km shallow seismic profiles are analyzed for sedimentary records of Yellow Sea in the past. Results show that the boundary of sediment transport between Korean side and Chinese side is about between $123^{\circ}E$ and $124^{\circ}E$. The similar result is produced from Shi et al. (in this publication). Two cyclonic patterns of surface sediments are recognized in the northeastern and southwestern Yellow Sea, while the strong front zone of the mud patch and sandy sediments are found in the southeastern Yellow Sea (the southwestern part of Korean coasts). The formation of fine-particle sediment packages, called for Northwest Mudbelt Deposit (NWMD), Hucksan Mudbelt Deposit (HSMD) and Jeju Mudbelt Deposit (JJMD), are resulted from eddies (gyres) of water circulations in the Yellow Sea. NWMD has been formed by cyclonic (anticlockwise) eddy. NWMD is composed of thick, homogeneous, relatively semi-consolidated gray clay-dominated deposit. On the other hand, HSMD and JJMD are formed by anticyclonic (clockwise) eddies. They are thick, homogeneous, organic-rich gray, silt-dominated deposit. Both core and surface sediments show that the middle zone across Chinese and Korean side contains bimodal frequency of grain-size distribution, indicating that two different transport mechanisms exist. These mud packages are surrounded by sand deposits from both Korea and China seas, indicating that Yellow Sea, which is the shallow sea and epicontinental shelf, is formed mostly by sand deposits including relict sands. The seismic profiles show such as small erosional/non-depositional channels, sand-ridges and sand-waves, Pleistocene-channelfilled deposits, a series of channels in the N-S major channel system, and thick Holocene sediment package, indicating that more complex sedimentary history exists in the Yellow Sea.

Regional difference in spontaneous firing inhibition by GABAA and GABAB receptors in nigral dopamine neurons

  • Kim, Yumi;Jang, Jinyoung;Kim, Hyun Jin;Park, Myoung Kyu
    • The Korean Journal of Physiology and Pharmacology
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    • v.22 no.6
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    • pp.721-729
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    • 2018
  • GABAergic control over dopamine (DA) neurons in the substantia nigra is crucial for determining firing rates and patterns. Although GABA activates both $GABA_A$ and $GABA_B$ receptors distributed throughout the somatodendritic tree, it is currently unclear how regional GABA receptors in the soma and dendritic compartments regulate spontaneous firing. Therefore, the objective of this study was to determine actions of regional GABA receptors on spontaneous firing in acutely dissociated DA neurons from the rat using patch-clamp and local GABA-uncaging techniques. Agonists and antagonists experiments showed that activation of either $GABA_A$ receptors or $GABA_B$ receptors in DA neurons is enough to completely abolish spontaneous firing. Local GABA-uncaging along the somatodendritic tree revealed that activation of regional GABA receptors limited within the soma, proximal, or distal dendritic region, can completely suppress spontaneous firing. However, activation of either $GABA_A$ or $GABA_B$ receptor equally suppressed spontaneous firing in the soma, whereas $GABA_B$ receptor inhibited spontaneous firing more strongly than $GABA_A$ receptor in the proximal and distal dendrites. These regional differences of GABA signals between the soma and dendritic compartments could contribute to our understanding of many diverse and complex actions of GABA in midbrain DA neurons.

Design of Fabrication of a Chip Antenna for DualB and Mobile Phone Application (듀얼밴드 휴대폰 응용을 위한 Chip 안테나 설계 및 제작)

  • Ko Young-hyuk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.7
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    • pp.1541-1547
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    • 2005
  • In this paper, Dualband internal antenna for GSM/DSC handset is proposed. The antenna has a size of about $38mm{\times}90mm{\times}1mm$, giving a total mobile phone PCB for support and fold type patch of about $30mm{\times}8mm{\times}3.2mm$. This antenna characteriatic facilitates the fine-tuning of the two operating frequencies of 909MHz and 1762MHz in the dualband design. The measured radiation pattern in the E-plane and H-plane for operating frequencies of 909MHz and 1762MHz is compared and analyzed. The designed and fabricated two band internal antenna for GSM/DSC handset have a gain between 0dBi and 2.0dBi at all bands. Also, the electric firld distribution and directivity on human head caused by portable phone is analyzed. An analysis model is composed of a human head model and the antenna mounted on the same ground plane as portable telephone size.