• Title/Summary/Keyword: ATC

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Assessment of the ATC Effect for Paddy Field and Forest Using Landsat Images and In-situ Measurement (Landsat영상과 현지조사에 의한 여름철 논과 산림의 기온저감효과 평가)

  • Park, Jong-Hwa;Na, Sang-Il;Kim, Jin-Soo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1943-1947
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    • 2007
  • The objective of this research was to find a direct and indirect method to estimate land surface temperature (LST) efficiently, using Landsat images and in-situ measurement. Agricultural fields including paddy fields have long been known to have multi-functions beneficial to the environment and ecology of the urban surrounding areas. Among these functions, the ambient temperature cooling (ATC) effect are widely acknowledged. However, quantitative and regional assessment of such effect has not had many investigations. Thermal remote sensing has been used over urban areas to assess ATC effect, to perform land cover classifications and as input for models of urban surface atmosphere exchange. Here, we review the use of thermal remote sensing in the study of paddy fields and urban climates, focusing primarily on the ATC effect. Landsat satellite images were used to determine the surface temperatures of different land cover types of a $441km^2$ study area in Cheongju, Korea. The results show that the ATC are a function of paddy area percentage in Landsat pixels. Pixels with higher paddy area percentage have more significant cooling effect.

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Analysis of the Relationship Between Land Cover and Land Surface Temperature at Cheongju Region Using Landsat Images in Summer Day (LANDSAT영상을 이용한 여름철 청주지역의 토지피복과 지표면온도와의 관계 분석)

  • Park, Jong-Hwa;Kim, Jin-Soo;Na, Sang-Il
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.5
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    • pp.39-48
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    • 2006
  • The objective of this research was to find an indirect method to estimate land surface temperature (LST) efficiently, using Landsat images. Agricultural fields including paddy fields have long been known to have multi-functions beneficial to the environment and ecology of the urban surrounding areas. Among these functions, the ambient temperature cooling (ATC) effect is widely acknowledged. However, quantitative and regional assessment of such effect has not been performed. Thermal remote sensing has been used over urban areas to assess the ATC effect, Thermal Island Effect(TIE), and as input for models of urban surface atmosphere exchange. Here, we review the use of thermal remote sensing in the study of paddy fields and urban climates, focusing primarily on the ATC effect. Landsat satellite images were used to determine the surface temperatures of different land cover types of a $44km^{2}$ study area in Cheongiu, Korea. The results show that the ATC is a function of paddy area percentage in Landsat pixels. Landsat pixels with higher paddy area percentage have much more cooling effect. The use of satellite data may contribute to a globally consistent method for analysis of ATC effect.

Protective Effect of Atractylodes macrocephala and Taraxacum spp. Combination Treatment in Balb/c Mice with Dextran Sulfate Sodium-Induced Ulcerative Colitis

  • Lee, Donghun;Kim, Hocheol
    • The Korea Journal of Herbology
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    • v.32 no.3
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    • pp.79-87
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    • 2017
  • Objectives : This study aimed to investigate the protective effects of an herbal mixture of Atractylodes macrocephala and Taraxacum spp. (ATC) on ulcerative colitis. We have previously screened traditional medicinal herbs to discover the effective candidate by the animal model. A. macrocephala and T. spp were identified as one of the effective herbs in the screening process. Methods : Experimental colitis was induced in male Balb/c mice by administering drinking water containing dextran sulfate sodium, which mimics the clinical and histological features of ulcerative colitis in human. ATC at doses of 30, 100 or 300 mg/kg were orally administered to mice twice per day for 10 consecutive days. To evaluate the damage from experimentla ulcerative colitis, body weight, colon length, disease activity index, myeloperoxidase and histological changes were measured and analyzed. Results : The administration of dextran sulfate sodium with drinking water resulted in markedly reduced colon length, severe body weight loss, increased levels of myeloperoxidase activity and histological damages in mice. ATC treatment significantly ameliorated the colon shortening, histological damage, body weight loss and disease activity index score in a dose-dependent manner. ATC also attenuated the colonic myeloperoxidase activity which reflects the severity and extent of inflammatory damage of colon. Conclusions : ATC exerts protective effects against inflammatory colonic structural damage induced by epithelial barrier integrity impairment. ATC also inhibits weight loss and related symptoms of UC which can be considered as the functional recovery of colon.

Enhanced Dissolution and Duodenal Permeation of Atorvastatin Calcium Using Bile Salt and 2-Hydroxypropyl-${\beta}$-Cyclodextrin (담즙산염과 2-히드록시프로필-${\beta}$-시클로덱스트린을 이용한 아토르바스타틴칼슘의 용출 및 십이지장 점막 투과 증진)

  • Choi, Ji-Won;Chun, In-Koo
    • YAKHAK HOEJI
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    • v.56 no.3
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    • pp.164-172
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    • 2012
  • This study was aimed to increase the solubility, dissolution and permeation rates of atorvastatin calcium (ATC) using bile salt and/or 2-hydroxypropyl-${\beta}$-cyclodextrin ($HP{\beta}CD$). From solubility studies, sodium deoxycholate (SDC) among bile salts studied was found to have the highest solubilizing effect on ATC ($4.4{\pm}0.4$ mg/ml), and the order of increasing solubility was SDC>sod. cholate>sod. glycocholate>sod. taurodeoxycholate>sod. taurocholate>conjugated bile acid. ATC solid dispersions were prepared at various ratios of drug to SDC and/or $HP{\beta}CD$, and evaluated by differential scanning calorimetry (DSC), dissolution studies and dissolution-permeation studies. DSC curves showed amorphous state of ATC in the physical mixture and solid dispersion. Dissolution rates of ATC-SDC solid dispersions and physical mixture were markedly increased at pH 6.8, but decreased at pH 1.2 with greater proportions of SDC due to the precipitation of SDC, compared with that of drug alone. On the other hand, dissolution rates of ATC-$HP{\beta}CD$ solid dispersion and physical mixture at pH 1.2 were varied with the ratio of drug to carriers. From duodenal permeation studies, it was found that fluxes of ATC (donor dose: 0.5 mg/3.5 ml) in the presence of 25 mM sodium glycocholate, SDC, sod. cholate and sod. taurocholate $(5.7{\pm}0.9$, $5.6{\pm}0.9$, $4.8{\pm}0.7$ and $4.6{\pm}0.9\;{\mu}g/cm^2/hr$, respectively) were enhanced, compared with drug alone ($3.4{\pm}0.9\;{\mu}g/cm^2/hr$). In the dissolution-permeation studies, 1 : 9 : 10 (w/w) ATC-SDC-$HP{\beta}CD$ solid dispersion increased the flux 2.2 times, compared with 1 : 5 : 4 (w/w) ATC-lactose-corn starch mixture as control. In conclusion, solid dispersions with bile salt and $HP{\beta}CD$ were found to be an effective means for increasing the dissolution and permeation rates of ATC.

Optimum Design of Braced Steel Framed Structures Considering Soil Condition Under Earthquake Loads (지반조건을 고려한 브레이스된 강골조 구조물의 내진 최적설계)

  • Park, Moon-Ho;Kim , Ki-Wook;Lee , Seung-Jo;Park , Jung-Hwal
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.10 no.4
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    • pp.97-107
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    • 2006
  • This study is structural analysis and continuous, discrete optimum design of braced steel frame structures under earthquake loads considering soil condition. The program which is able to perform simultaneously structural analysis and continuous, discrete optimum design, it is applied steel frame structures using unbraced, Z-braced, and X-braced types and analyze the program about static loads and seismic loads. The purpose of this study is to present proper braced type for seismic effects by comparing and analyzing results of analytic method about various cases using specially Newmark-Hall design spectrum, ATC design spectrum and ATC equivalent static analysis and finding minimum weight and design variables which satisfy the ultimate strength requirements of AISC-ASD specifications, the serviceability requirements and allowable story drift requirements of ATC-3-06 and various constraints.

Evaluation of Seismic Performance Factors of Diagrid Structural System (다이아그리드 구조 시스템의 내진성능계수 평가)

  • Kim, Kyoung-Hwan;Ju, Young-Kyu;Kim, Sang-Dae
    • Journal of Korean Society of Steel Construction
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    • v.22 no.3
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    • pp.229-239
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    • 2010
  • As a new structural system, the diagrid system resists both gravity and lateral loads with diagonal columns. In current seismic design provisions, however, the response modification factor for a new structural system is not provided yet. ATC-63 provides a new methodology for defining various seismic performance factors, including the response modification factor. ATC-63 includes the collapse margin ratio in modifying the response modification factor, which can vary with many structural systems. In this paper, a non-linear static analysis and a dynamic analysis were conducted for four different diagrid models with 4-to 36-story heights. From these analyses, the response modification factor of the diagrid system was evaluated.

Clinical Characteristics and Prognosis of Differentiated Thyroid Carcinoma with Small Foci of Anaplastic Transformation

  • Ahn, Hwa Young;Jung, Kyeong Choen;Park, Do Joon;Park, Young Joo;Cho, Bo Youn
    • International journal of thyroidology
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    • v.10 no.2
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    • pp.96-101
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    • 2017
  • Background and Objectives: Anaplastic thyroid carcinoma (ATC) is commonly related with concurrent differentiated thyroid carcinoma (DTC). We aimed to examine the clinicopathologic characteristics, prognosis and gene expression of DTC with anaplastic foci. Materials and Methods: Eighteen patients with DTC with anaplastic foci were enrolled in this study. To compare the clinicopathologic characteristics and prognosis of anaplastic foci subjects with conventional ATC or DTC, we additionally included 12 ATC and 1030 DTC patients who diagnosed during same period. Immunohistochemistry was performed to check the gene expression in anaplastic foci and DTC component. Results: In anaplastic foci group, tumor size was larger ($2.5{\pm}1.3$ vs. $1.2{\pm}0.9cm$, p=0.001), distant metastasis was more frequent (11.1 vs. 0%, p=0.000) and 1-year survival rate was low (88.9 vs. 100%, p=0.000) than DTC group. In contrast, compared with ATC group, anaplastic foci group showed younger age at diagnosis ($50{\pm}16$ vs. $63{\pm}18years$, p=0.039), smaller tumor size ($2.5{\pm}1.3$ vs. $3.8{\pm}1.4cm$, p=0.027), less distant metastasis (11.1 vs. 41.7%, p=0.084) and longer 1-year survival rate (88.9 vs. 25.0%, p=0.001). Expression of p53 protein was observed in 100% of anaplastic foci, ATC and 12.5% of papillary thyroid carcinoma component. Conclusion: DTC with foci of anaplastic transformation has a worse prognosis than DTC, but a better prognosis than ATC. Our results support that DTC with anaplastic foci was intermediate state from DTC to ATC.

Isolation of Bacillus amyloliquefaciens ATC6 Producing Acidic Cellulase (산성 Cellulase를 분비하는 Bacillus amyloliquefaciens ATC6의 분리)

  • Lee, Se-Hyung;Chae, Jong-Pyo;Kim, Min-Jeong;Kang, Dae-Kyung
    • Journal of Animal Science and Technology
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    • v.52 no.1
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    • pp.65-70
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    • 2010
  • A bacterium producing acidic cellulase was isolated from pig feces. The isolate, ATC6 strain, was found to be Gram-positive, non-motile, catalase-positive, and spore-forming stain. Under an electron microscope, the cells were observed to be rod-shaped. The isolate was identified as Bacillus amyloliquefaciens ATC6 on the basis of morphological and biochemical properties as well as 16S rRNA gene sequences. Optimum pH and temperature for the cellulase activity of the culture supernatant of B. amyloliquefaciens ATC6 were found to be pH 4.5 and $55^{\circ}C$, respectively. More than 80% of its maximum activity was maintained at pH 4.0. The cellulase activity was maintained at temperatures ranging from 35 to $55^{\circ}C$ after 2 h incubation at pH 4.5, whereas it's activity decreased rapidly at $65^{\circ}C$.

A Case Study on Improving for Operating ATC/ATO System and Driving Environment Using FMECA (FMECA를 활용한 ATC/ATO 시스템 및 운전환경 개선 사례연구)

  • Kim, Hanyoung;Lee, Jinchoon
    • Journal of the Korean Society for Railway
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    • v.15 no.6
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    • pp.550-557
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    • 2012
  • In general, FMECA is a technique for identifying failure modes and devices which could result in fatal outcomes. Also it can be used in design or in maintenance through establishing priorities. The purpose of this paper is aimed at improving the driving conditions in advance through analyzing the operation failure phenomena quantitatively with FMECA analysis on the onboard signal system equipped with ATC/ATO, and through deriving the risk factors. This paper suggests an alternative solution for improving the performance of ADU by analyzing a case with FMECA.

Seismic performance of a wall-frame air traffic control tower

  • Moravej, Hossein;Vafaei, Mohammadreza;Abu Bakar, Suhaimi
    • Earthquakes and Structures
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    • v.10 no.2
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    • pp.463-482
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    • 2016
  • Air Traffic Control (ATC) towers play significant role in the functionality of each airport. In spite of having complex dynamic behavior and major role in mitigating post-earthquake problems, less attention has been paid to the seismic performance of these structures. Herein, seismic response of an existing ATC tower with a wall-frame structural system that has been designed and detailed according to a local building code was evaluated through the framework of performance-based seismic design. Results of this study indicated that the linear static and dynamic analyses used for the design of this tower were incapable of providing a safety margin for the required seismic performance levels especially when the tower was subjected to strong ground motions. It was concluded that, for seismic design of ATC towers practice engineers should refer to a more sophisticated seismic design approach (e.g., performance-based seismic design) which accounts for inelastic behavior of structural components in order to comply with the higher seismic performance objectives of ATC towers.