• Title/Summary/Keyword: Meta-Research

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The comparative analysis of KOMPSAT-3 based surface normalized difference vegetation index: Application of GeoEye data (다목적실용위성 3호의 지표 정규식생지수 산출 및 비교 분석: GeoEye 자료 활용)

  • Yeom, Jong-Min
    • Aerospace Engineering and Technology
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    • v.13 no.2
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    • pp.80-86
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    • 2014
  • In this study, we the estimated surface normalized difference vegetation index by using the KOrea Multi-Purpose SATellite-3 (KOMPSAT-3) multi-spectral images for comparative analysis. The estimated NDVI from KOMPSAT-3 is used as for comparison with the high resolution GeoEye products. The geometry conditions for atmospheric effects are selected from meta files of KOMPSAT-3 bundle data. The used geometry conditions are consist of solar zenith angle, solar azimuth angle, viewing zenith angle, viewing azimuth angle, and date. And, Atmospheric effects such as attenuation, scattering and absorption were physically simulated from water vapor, ozone and aerosol information. Generally, although ground measurements are important for accurate information, in this study, MODIS atmospheric products are used as atmospheric constituents. The surface reflectance from radiative transfer model is utilized for estimating vegetation index. The present study, to reduce atmospheric and geometry conditions between KOMPSAT-3 and GeoEye having difference observation characteristics, data acquisition time is carefully determined for reliable vegetation spectral characteristics.

Effects of NaOH and Na2SiO3·9H2O Addition on Strength Development of Class F Fly Ash-Mortar (F급 플라이 애쉬-모르타르의 강도발현에 대한 NaOH과 Na2SiO3·9H2O 첨가의 영향)

  • Park, Sang-Sook;Kang, Hwa-Young;Han, Sang-Ho;Kang, Hee-Bog
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.4
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    • pp.261-269
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    • 2005
  • The object of this research is to produce alkali activated fly ash-cement using low calcium fly ash as substitute for portland cement. The experimental program included activation of fly ash by a strong base(NaOH) at different concentration, temperature, and liquid-to-fly ash ratios. To achieve for higher compressive strength of the hardened product, sodium meta silicate is added to the alkaline solution. From the factors considered on strength development, the ratio of liquid/fly ash, the activator concentration and temperature always result to be significative factors. The optimization studied show that the alkaline solution concentration of $NaOH(210g)+Na_2SiO_3{\cdot}9H_2O(30g)+H_2O=1L$ at $50^{\circ}C$ produces the best alkali activation effect for the low calcium fly ash. SEM and XRD patterns showed that the components of alkali-activated fly ash consist mainly of mullite, quartz and amorphous aluminosilicate.

A Strategy for Activating Spatial Data Community : A Case of the NSDI CAP(Cooperative Agreements Program) in U.S. (공간정보 커뮤니티 활성화 방안 연구 : 미국 NSDI의 CAP 사례를 중심으로)

  • Kim, Ho-Yong;Nam, Kwang-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.1
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    • pp.26-39
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    • 2011
  • This paper reviews the strategy of activating spatial data community and its impacts, focusing on the Cooperative Agreements Program(CAP) of National Spatial Data Infrastructure(NSDI), established by Federal Geographic Data Committee(FGDC) in U.S. to facilitate cooperative data sharing. After thoroughly reviewing the 20 research categories followed by 350 cases, supported by CAP for the last decade, it turned out that since NSDI issued "Future Directions Initiative" in 2004, the CAP adopted all components of NSDI as CAP categories in attempting to reinforce the partnership rather than mainly deploying standardized meta-data. Also, CAP has been utilized as a means to enforce the role of NSDI as spatial data user and provider as well, recognizing that the spatial data community is essence for expandable and sustainable NSDI. Implementing CAP resulted in the sound structure of spatial data marketplaces increasing spatial data demand and promoting the relevant business due to diverse users.

Synthesis of Dihydroxylated Chalcone Derivatives with Diverse Substitution Patterns and Their Radical Scavenging Ability toward DPPH Free Radicals

  • Kim, Beom-Tae;O, Kwang-Joong;Chun, Jae-Chul;Hwang, Ki-Jun
    • Bulletin of the Korean Chemical Society
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    • v.29 no.6
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    • pp.1125-1130
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    • 2008
  • A series of dihydroxylated chalcone derivatives with diverse substitution patterns on a phenyl ring B and the para-substituents on a phenyl ring A were prepared, and their radical scavenging activities were evaluated by simple DPPH test to determine quantitative structure-activity relationship in these series of compounds. The chalcone compounds with the ortho- (i.e. 2',3'- and 3',4'-) and para- (i.e. 2,5'-) substitution patterns show an excellent antioxidant activities (80-90% of control at the concentration of 50 $\mu$M) which are comparable to those of ascorbic acid and $\alpha$ -tocopherol as positive reference materials. On the contrary, the compounds with meta- (i.e. 2',4'-, 3',5'-) substitution pattern demonstrate very dramatic decrease in activities which are around 25% of the control even at the concentration of 200 $\mu$ M (IC50 > 200 $\mu$ M). These dramatic differences could be interpreted in terms of the ease formation of fairly stable semiquinone radicals from the ortho- and parasubstituted chalcone molecules through facilitating electron delocalization. Our results indicate that the substitution patterns of two hydroxyl groups on ring B are very important structural factors for their radical scavenging activity enhancement. Meanwhile, the substituents at para-position of the phenyl ring A of chalcones have no influence on the activity.

The Revised Korean Practice Parameter for the Treatment of Attention-Deficit Hyperactivity Disorder (III) - Pharmacological Treatment - (주의력결핍 과잉행동장애 한국형 치료 권고안 개정안(III) - 약물치료 -)

  • Kim, Hyo-Won;Kim, Eunjoo;Kim, Ji-Hoon;Park, Jangho;Bahn, Geon Ho;Lee, Yeon Jung;Jhung, Kyungun;Shin, Dongwon
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.28 no.2
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    • pp.70-83
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    • 2017
  • The objective of this review is the revision of the Korean practice parameters for the pharmacological treatment of attention-deficit hyperactivity disorder (ADHD) based on the change in the diagnostic system from DSM-IV-TR to DSM-5 and psychopharmacological developments. For the evidence-based approach, the authors conducted a review of the literature, including controlled clinical trials, studies of the side effects of drugs, toxicology and meta-analyses from the United States and Europe, as well as recent research conducted in Korea. The review committee composed of Korean experts on ADHD reviewed the revised parameters. This revised version reveals how to use central nervous system psychostimulants, non-stimulants such as atomoxetine and alpha2 agonists, and other medication for ADHD, and how to manage the adverse effects of such medication. At the end of this revised version, the authors propose recommendations for the pharmacotherapy of ADHD.

Reduction of Acoustic Resonance Phenomena in Pulse Start MetalHalide Lamp (MH200W) (고효율 펄스스타트 메탈핼라이드램프(MH200W)의 음향공명현상감소)

  • 김기정
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.15 no.6
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    • pp.8-14
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    • 2001
  • MetalHalid lamps have good efficiency, good color rendition and good focusing capability. But the shortcoming of metalhalid lamps is blown as acoustic resonance phenomena in the arc tube. Such acoustic resonance produce annoying fluctuations in the intensity and distribution of the emitted light, they can raise the voltage to the point where the arc is extinguished and they can move the arc close enough to the wall to cause local overheating and tube cracking. The objective of this research is to reduce acoustic resonance in the arc tube of the Pulse Start MetaIHaide lamp(MH200[W]). To reduce the acoustic resonance phenomena the electronic ballast was designed for high frequency operation with the constant frequency sinusoidal wave of 89[kHz] in the 84.6[kHz]∼94.2[kHz] range. Experimental results show that the acoustic resonance phenomena are not in the arc tube of Pulse Start MetalHalide lamp (MH200[W]) .

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The Effect of Walking Exercise Program on Cardiorespiratory Function and Flexibility in Elderly Women (걷기운동프로그램이 노인여성의 심폐기능, 유연성에 미치는 효과)

  • 신윤희;최영희
    • Journal of Korean Academy of Nursing
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    • v.26 no.2
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    • pp.372-386
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    • 1996
  • Recently, the ratio of elderly in the population are fast growing due to socio-economical development and the better medical service. Proportionally, the health problems in elderly are increasing, too. Medical professionals must try so that the elderly have the better life through health promotion and disease prevention as well as disease treatment. This study evaluated the effect of walking exercise program on the cardiorespiratory function and the flexibility in the elderly women. The design of research was one group pretest-posttest design. The subjects were eleven elderly women over sixty years old to live in K-city, Kyonggi-do. The type of exercise was walking, which was the most popular exercise in questionnaire. The exercise intensity was 40%∼60% of the target heart-rate by Karvonen's method and maintained by the heart-rate monitor. The exercise period was five weeks and the exercise frequency was three times per week. The exercise duration was forty minutes at first and gradually increased up to an hour. In order to evaluate the effect of walking exercise, we measured VO/sub₂ max, resting heart -rate, systolic/diastolic blood pressure, FVC, FEV/sub₁, the flexibility before and after the five week's exercise program. The data are analyzed by the paired t-test and Wilcoxon signed rank test using SAS package. The results are as follows : 1) The hypothesis that cardiorespiratory function will be improved was partly supported. In VO/sub₂ max(p=0.0001), resting heart-rate(p=0.0030), systolic/diastolic blood-pressure(p=0.0387/ p=0.0024), there was significant difference. FVC and FEV/sub₁ were increased after the exercise, but there were no significant difference. 2) The hypothesis that the flexibility will be improved was supported. There was significant difference in the flexibility(p=0.0140). As the further study, it is necessary to reevaluate the effect with more refined design. We also need to try meta-analysis about the results of previous studies obtained in the experimental setting and compare our result obtained in the field setting with them.

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Analysis of the current situation of Affective Characteristics of Korean Students Based on the Results of PISA and TIMSS (PISA와 TIMSS 결과에 나타난 우리나라 학생의 정의적 성취 실태 분석 - 수학 교과를 중심으로 -)

  • Choe, Seung-Hyun;Park, Sangwook;Hwang, Hye Jeang
    • Journal of the Korean School Mathematics Society
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    • v.17 no.1
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    • pp.23-43
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    • 2014
  • This study aims to develop strategies for improving the affective characteristics of Korean students based on results from international achievement tests. In pursuing the goal, different research methods are employed including a) analysis of the theories and literature regarding the affective domains included in PISA and TIMSS studies; b) analysis of the current situation and needs of Korean students with respect to the affective factors based on PISA and TIMSS results; c) case studies of best practices in relation to students' affective domains in Korea and abroad; and d) development of strategies for improving and supporting Korean students' affective characteristics. Especially, this paper describes meta-analyses of the results from the previous PISA and TIMSS studies. Afterwards, it reports statistical analyses results on the relationship between students' affective achievements and educational context variables. Data from TIMSS 2011, TIMSS 2007, PISA 2006, and PISA 2003 are used for the analyses, and contextual variables are selected through rigorous statistical analyses including frequency and correlation, and expert consultation. The effects of educational contextual variables on students' affective achievement in mathematics and science are analyzed through Hierarchical Linear Model.

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5-FU or capecitabine based chronomodulated chemotherapy for advanced colorectal cancer: mata-analysis and systematic review (진행성 대장직장암 환자군에 있어서 5-FU 혹은 capecitabine의 최적 시간 치료법에 대한 체계적 고찰 : 메타분석)

  • Lee, Jee Young;Oh, Hye Kyung;Ryu, Han Sung;Yoon, Seong Woo
    • Journal of Korean Traditional Oncology
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    • v.20 no.1
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    • pp.31-44
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    • 2015
  • Background : The purpose of this study is to investigate the efficacy and safety of the circadian delivery schedule of fluorouracil or capecitabine based chemotherapy for advanced colorectal cancer. Patients and methods : A meta-analysis was performed using individual data from eight international randomized clinical trials, especially phase II or III trials, comparing 5-fluorouracil, or capeticabine in chronomodulated or conventional schedule. The data from 8 studies was composed of 692 patients receiving chronomodulated chemotheray and 684 patients receiving conventional chemotherapy. The main end point was response rate. Results : Response rate was insignificantly different from each group (RR 1.14, 95%CI 0.74-1.74, p=0.55). Overall survival and progresseion-free survival were not significant either. Chemotherapy induced anemia, diarrhea, and nausea/vomiting were worse in the chronotherapy group, with statistic significance respectively. On the other hand, chemotherapy induced thrombocytopenia, stomatitis, peripheral neuropathy, and dermatotoxicity were better but they were not statistically significant results. Conclusions : Patients lived longer but not significantly on chronomodulated chemotherapy rather than on conventional chemotherapy. Patients on chronomodulated chemotherapy experienced adverse events more. The chronomodulated chemotherapy schedule needs adjustment of its delivery schedule and further research is required.

Cloning and Expression of pcbC and pcbD Genes Responsible for 2,3-Dihydroxybiphenyl Degradation from Pseudomonas sp. P20

  • Nam, Jung-Hyun;Oh, Hee-Mock;Kim, Chi-Kyung
    • Journal of Microbiology and Biotechnology
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    • v.5 no.2
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    • pp.68-73
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    • 1995
  • Pseudomonas sp. P20 was shown to be capable of degrading biphenyl and 4-chlorobiphenyl (4CB) to produce the corresponding benzoic acids wnich were not further degraded. But the potential of the strain for biodegradation of 4CB was shown to be excellent. The pcbA, B, C and D genes responsible for the aromatic ring-cleavage of biphenyl and 4CB degradation were cloned from the chromosomal DNA of the strain. In this study, the pebC and D genes specifying degradation of 2, 3-dihydroxybiphenyl (2, 3-DHBP) produced from biphenyl by the pebAB-encoded enzymes were cloned by using pBluescript SK(+) as a vector. From the pCK102 (9.3 kb) containing pebC and D genes, pCK1022 inserted with a EcoRI-HindIII DNA fragment (4.1 kb) carrying pebC and D and a pCK1092 inserted with EcoRI-XbaI fragment (1.95 kb) carrying pebC were constructed. The expression of pcbC and D' in E. coli CK102 and pebC in E. coli CK1092 was examined by gas chromatography and UV-vis spectrophotometry. 2.3-dihydroxybiphenyl was readily degraded to produce meta-cleavage product (MCP) by E. coli CK102 after incubation for 10 min, and then only benzoic acid(BA) was detected in the 24-h old culture. The MCP was detected in E. coli CK1022 containing pebC and 0 genes (by the resting cells assay) for up to 3 h after incubation and then diminished completely in 8 h, whereas the MCP accumulated in the E. coli CK1092 culture even after 6 h of incubation. The 2, 3-DHBP dioxygenases (product of pebC gene) produced by E. coli CK1, CK102, CK1023, and CK1092 strains were measured by native PAGE analysis to be about 250 kDa in molecular weight, which were about same as those of Pseudomonas sp. DJ-12, P. pseudoa1caligenes KF707, and P. putida OU83.

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