• 한국지구과학회지
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• 제25권8호
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• pp.764-773
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• 2004

산불지역 토양의 침식양상을 구분하기위하여 강원도 강릉시 사천면 일대의 산불지역 토양을 조사하였다. 토양은 유기물의 분포양상 및 토양층의 두께, 토양층 발달의 완전성(성숙도)를 근거로 5개 유형으로 구분하였다. 침식 현상은 토양의 유형에 따라 다르게 나타났다. 나뭇잎, 낙엽층, 뿌리, 재 그 밖의 유기물의 피복이 토양의 색과 영상 이미지 반사에 영향을 미치는 중요한 요인이었다. 침식양상의 차이를 보이는 5개 유형의 토양의 Landsat ETM 영상은 토양 유형별로 상이한 반사특성을 보였다. 산불지역 토양의 정규식생지수(NDVI)와 무감독 분류는 토양유형에 따른 Landsat ETM 영상 차이를 잘 반영하기 못하였으나, 최대우도법에 의한 감독분류 기법의 적용시 산불지역에서 침식형태에 따른 토양유형 구분이 가능하였다. 본 연구는 산불지역에서 침식현상을 파악하고 예측하는데 Landsat ETM 영상의 활용이 매우 효과적임을 보여주었다.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.138-140
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• 2002

The spinal cord dose is the one of the limiting factor for the radiation treatment of the head & neck (H&N) or the thorax region. Due to the fact that the cord is the elongated shaped structure, it is not an easy task to maintain the cord dose within the clinically acceptable dose range. To overcome this problem, the spinal cord partial block technique (PBT) with the dynamic Multi-Leaf Collimator (dMLC) has been developed. Three dimension (3D) conformal beam directions, which minimize the coverage of the normal organs such as the lung and the parotid gland, were chosen. The PBT field shape for each field was designed to shield the spinal cord with the dMLC. The transmission factors were determined by the forward calculation method. The plan comparisons between the conventional 3D conformal therapy plan and the PTB plan were performed to evaluate the validity of this technique. The conformity index (CI) and the dose volume histogram (DVH) were used as the plan comparison indices. A series of quality assurance (QA) was performed to guarantee the reliable treatment. The QA consisted of the film dosimetry for the verification of the dose distribution and the point measurements. The PBT plan always generated better results than the conventional 3D conformal plan. The PBT was proved to be useful for the H&N and thorax region.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제28권3호
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• pp.183-189
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• 2017

Objectives: The study aimed to identify the characteristics of attention-deficit hyperactivity disorder (ADHD) that was not diagnosed in childhood or adolescence, but only in adulthood. Methods: The characteristics of patients diagnosed with ADHD in adulthood were compared with those of patients diagnosed in childhood were assessed via a retrospective review of the medical records at one university hospital from 2005 to 2013. If the age at which they were confirmed as having ADHD was less than 19 years old, they were grouped as childhood-diagnosed group (CD); if they were 19 years old or more, they were grouped as adulthood-diagnosed group (AD). Results: The CD and AD included 50 (46.3%) and 58 (53.7%) patients, respectively. Inattention was the most common symptom in both groups. Behavioral and emotional problems were the second most frequent symptoms in the CD and AD, respectively. The intelligent quotient was significantly higher in the AD than in the CD. The most common comorbidity was depression in the CD and personality disorder in the AD. The most common reason for visiting the hospital was referral by acquaintances in the CD and media coverage in the AD. Conclusion: Clinicians should put ADHD on the index of suspicion when they examine adults with various psychiatric symptoms, because the diagnosis of ADHD might have been missed in childhood and the symptoms of ADHD might have changed as they grew up.

• 한국환경복원기술학회지
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• 제15권6호
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• pp.79-89
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• 2012

This study was compared to the differences in the habitat, species composition and community structure of revegetation and nature area in Korea. Plant number in plot of revegetation and nature area was 10.3 and 15.0 taxa, respectively, and coverage was 90.6 and 88.1%, respectively. Revegetation and nature area was very heterogeneous, due to low similarity index (0.38) and less common plants. Festuca arundinacea frequency (56.7%) was highest in revegetation area, and Oplismenus undulatifolius frequency (66.7%) was highest in nature area. Plant appearing of revegetation and nature area was 111 and 136 taxa, respectively. Herb appearing of revegetation and nature areas was 93 (83.3%) and 72 (52.9%) taxa, respectively, tree was 18 (16.2%) and 64 (47.1%) taxa, respectively. Plant communities of revegetation area was classified into Lespedeza bicolor, Indigofera amblyantha, Alnus sibirica, Festuca arundinacea, Eragrostis curvula, Miscanthus sinensis, Humulus japonicus, Setaria faberii, Rudbeckia bicolor, Pueraria lobata community. Plant communities of nature area was classified into Pinus densiflora, Quercus aliena, Quercus acutissima, Quercus variabilis, Quercus serrata, Castanea crenata, Pinus rigida, Robinia pseudoacacia, Populus tomentiglandulosa, Phyllostachys bambusoides community. Habitat, species composition and community structure of revegetation and nature area showed a large difference.

• 대한공간정보학회지
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• 제21권2호
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• pp.85-92
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• 2013

본 연구에서는 GOSAT으로부터 측정된 이산화탄소 농도와 이산화탄소의 분포에 영향을 미치는 토지피복, 식생지수 등을 GIS 공간분석기법과 연계하여 동북아시아 지역 이산화탄소의 공간적 분포 특성을 규명하였다. 그 결과 이산화탄소의 공간적 분포는 그 주변지역의 토지이용현황에 따라 그 패턴을 달리한다는 사실을 가시적으로 확인할 수 있었으며 이산화탄소는 도시와 같은 개발지에서 높은 농도대를 형성하는 반면 산림지역에서는 낮게 나타나고 있음을 확인할 수 있었다. 또한 이산화탄소와 식생 간에는 통계적으로 유의한 수준에서 비교적 높은 부(-)의 상관관계가 존재함을 확인할 수 있었다. 이는 향후 온실가스 저감 대책 및 완화를 위한 계획 수립에 있어 그 기초자료로 활용되어 질 수 있을 것으로 판단된다.

• 한국환경복원기술학회지
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• 제18권3호
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• pp.65-77
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• 2015

The urban park has important functions as a habitat for wildlife as well as open space of rest and community for people. This study was carried out to find what factors of structure and vegetation of urban parks could affect forest bird species diversity in Cheonan city. The study surveyed bird and vegetation species in 26 urban parks, Cheonan city. A correlation analysis and multiple linear regressions were performed to test whether habitat structure and vegetation were the major correlate with species diversity. The results showed the Dujeong park was the most high bird species diversity (H' = 2.13), and the Dujeong-8 park (H' = 2.02) and the Cheongsa park (H' = 1.73) were considerably higher than the other urban parks. The variables that were strongly correlated with bird species diversity were park area, number of subtree species, canopy of shrub, number of shrub species, shape index, canopy of subtree, canopy of tree, and impervious surface ratio. The regression of bird species diversity against the environmental variables showed that 3 variables of park area, canopy of subtree, and canopy of tree were included in the best model. Model variable selection was broadly similar for the 5 optimal models. It means park area and multi-layer vegetation were the most consistent and significant predictor of bird species diversity, because urban parks were isolated by built-up areas. Especially the subtree coverage that provides shelter and food for forest birds was an important variable. Therefore, to make parks circular-shaped and abundant multi-layer vegetation, which could be a buffer to external disturbances and improve the quality of habitats, may be used to enhance species diversity in creation and management of urban parks.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.556-559
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• 2007

The Urban Environmental Quality (UEQ) indicates a complex and various parameters resulting from both human and natural factors in an urban area. Vegetation, climate, air quality, and the urban infrastructure may interact to produce effects in an urban area. There are relationships among air pollution, vegetation, and degrading environmental the urban heat island (UHI) effect. This study investigates the application of multi-spectral remote sensing data from the Landsat ETM and TM sensors for the mapping of air quality and UHI intensity in Seoul from 2000 to 2006 in fine resolution (30m) using the emissivity-fusion method. The Haze Optimized Transform (HOT) correction approach has been adopted for atmospheric correction on all bands except thermal band. The general UHI values (${\Delta}(T_{urban}-T_{rural})$) are 8.45 (2000), 9.14 (2001), 8.61 (2002), and $8.41^{\circ}C$ (2006), respectively. Although the UHI values are similar during these years, the spatial coverage of "hot" surface temperature (>$24^{\circ}C$) significantly increased from 2000 to 2006 due to the rapid urban development. Furthermore, high correlations between vegetation index and land surface temperature were achieved with a correlation coefficients of 0.85 (2000), 0.81 (2001), 0.84(2002), and 0.89 (2006), respectively. Air quality is shown to be an important factor in the spatial variation of UEQ. Based on the quantifiable fine resolution satellite image parameters, UEQ can promote the understanding of the complex and dynamic factors controlling urban environment.

• Journal of Trauma and Injury
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• 제25권4호
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• pp.241-246
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• 2012

Purpose: The objective of this study was to investigate the appropriateness of the cross table lateral cervical X-ray used in the emergency department for severely traumatized Korean patients. Methods: Patients visiting our institution from May 2011 to May 2012, who had injury severity score (ISS) > 15 and who received a cervical X-ray in the emergency department, were included in this study. Data including demographics, ISS score, GCS score, and place where the x-ray was taken were collected to evaluate their relationship with appropriate coverage of the cervical X-ray. The appropriateness of a cervical cross lateral view X-ray was evaluated using exposure of the basion, and the opisthion, as well as the distal level of exposure. Results: Fifty-two patients were included in this study. The identification rate of the basion was 79.2%, and the identification rate of the opisthion was 88.7%. Complete exposure of C7/T1 was accomplished in 3.8% of the patients. The ISS was higher for X-ray taken in the trauma bay, but the range of exposure showed no difference between the places where the X-rays taken. Patients who had exposure of C 5/6 or more had lower body weight and body mass index (BMI) compared with unexposed patients. Conclusion: In severely traumatized Korean patients, the adequacy of the cross table lateral cervical X-ray was inappropriate in most cases. No difference was observed in the exposure range between the places where the X-rays were taken, and patients with less exposure showed higher body weight and higher BMI.

• 한국농림기상학회지
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• 제6권1호
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• pp.49-60
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• 2004

Northern Gyeonggi Province(NGP), consisting of 3 counties, is the northernmost region in South Korea adjacent to the de-militarized zone with North Korea. To supplement insufficient spatial coverage of official climate data and climate atlases based on those data, high-resolution digital climate models(DCM) were prepared to support weather- related activities of residents in NGP Monthly climate data from 51 synoptic stations across both North and South Korea were collected for 1981-2000. A digital elevation model(DEM) for this region with 30m cell spacing was used with the climate data for spatially interpolating daily maximum and minimum temperatures, solar irradiance, and precipitation based on relevant topoclimatological models. For daily minimum temperature, a spatial interpolation scheme accommodating the potential influences of cold air accumulation and the temperature inversion was used. For daily maximum temperature estimation, a spatial interpolation model loaded with the overheating index was used. Daily solar irradiances over sloping surfaces were estimated from nearby synoptic station data weighted by potential relative radiation, which is the hourly sum of relative solar intensity. Precipitation was assumed to increase with the difference between virtual terrain elevation and the DEM multiplied by an observed rate. Validations were carried out by installing an observation network specifically for making comparisons with the spatially estimated temperature pattern. Freezing risk in January was estimated for major fruit tree species based on the DCMs under the recurrence intervals of 10, 30, and 100 years, respectively. Frost risks at bud-burst and blossom of tree flowers were also estimated for the same resolution as the DCMs.

• Journal of Biosystems Engineering
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• 제42권4호
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• pp.258-264
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• 2017

Purpose: This study determines the spray characteristics and effective spray width of a tractor-mounted commercial boom sprayer through experiments. Methods: Performance tests were conducted to investigate the spray characteristics of the nozzles on a commercial boom sprayer. The flow rate and spray width of a single nozzle were measured at three levels of spray pressure (0.5, 0.7, and 1.0 MPa) and spray height (15, 30, and 45 cm), respectively. The average value of three repetition tests was used as the representative value. A coefficient of variation (CV) was used as an index of spray uniformity, and the width that guarantees CV values of approximately 15% was determined as the effective spray width. The spray characteristics of the overall boom sprayer were derived analytically by superimposing the spray characteristics of a single nozzle. Results: The test results for a single nozzle showed that the spray width tended to increase as the spray height and spray pressure increased. The effective spray width for a single nozzle was the largest at a spray pressure of 1.0 MPa and spray height of 45 cm, which resulted in a coverage of 84 cm of width. The effective spray width for the entire boom sprayer was also the largest at the spray pressure of 1.0 MPa and spray height of 45 cm, with a magnitude of 424.5 cm. The chemical spraying work in an actual field was simulated by applying a spray width of 400 cm. As a result of the operation for three swaths, the CV value was less than 10% for 1,200 cm of the overall spray width, which meant that uniform application was achieved. Conclusions: It was reasonable to set the effective spray width of the boom sprayer used in this study to 400 cm.