• Title/Summary/Keyword: co-validation

Search Result 436, Processing Time 0.026 seconds

Comparison of Model-simulated Atmospheric Carbon Dioxide with GOSAT Retrievals

  • Shim, Chang-Sub;Nassar, Ray;Kim, Jhoon
    • Asian Journal of Atmospheric Environment
    • /
    • v.5 no.4
    • /
    • pp.263-277
    • /
    • 2011
  • Global atmospheric $CO_2$ distributions were simulated with a chemical transport model (GEOS-Chem) and compared with space-borne observations of $CO_2$ column density by GOSAT from April 2009 to January 2010. The GEOS-Chem model simulated 3-D global atmospheric $CO_2$ at $2^{\circ}{\times}2.5^{\circ}$ horizontal resolution using global $CO_2$ surface sources/sinks as well as 3-D emissions from aviation and the atmospheric oxidation of other carbon species. The seasonal cycle and spatial distribution of GEOS-Chem $CO_2$ columns were generally comparable with GOSAT columns over each continent with a systematic positive bias of ~1.0%. Data from the World Data Center for Greenhouse Gases (WDCGG) from twelve ground stations spanning $90^{\circ}S-82^{\circ}N$ were also compared with the modeled data for the period of 2004-2009 inclusive. The ground-based data show high correlations with the GEOS-Chem simulation ($0.66{\leq}R^2{\leq}0.99$) but the model data have a negative bias of ~1.0%, which is primarily due to the model initial conditions. Together these two comparisons can be used to infer that GOSAT $CO_2$ retrievals underestimate $CO_2$ column concentration by ~2.0%, as demonstrated in recent validation work using other methods. We further estimated individual source/sink contributions to the global atmospheric $CO_2$ budget and trends through 7 tagged $CO_2$ tracers (fossil fuels, ocean exchanges, biomass burning, biofuel burning, net terrestrial exchange, shipping, aviation, and CO oxidation) over 2004-2009. The global $CO_2$ trend over this period (2.1 ppmv/year) has been mainly driven by fossil fuel combustion and cement production (3.2 ppmv/year), reinforcing the fact that rigorous $CO_2$ reductions from human activities are necessary in order to stabilize atmospheric $CO_2$ levels.

Development and validation of a selective and sensitive LC-MS/MS method for determination of misoprostol acid in human plasma: Application to bioequivalence study

  • Park, Yong Sun;Kim, Keun Nam;Kim, Ye Na;Kim, Jung Hwan;Kim, Jin Young;Sim, Soo Ji;Lee, Heon Soo
    • Analytical Science and Technology
    • /
    • v.28 no.1
    • /
    • pp.17-25
    • /
    • 2015
  • A rapid, sensitive and specific method was developed and validated using electrospray ionization (ESI) tandem mass spectrometry (LC-MS/MS) for determination of misoprostol acid in human plasma. Misoprostol $acid-d_5$ was used as in internal standard (IS). The analyte and IS were extracted by simple one step solid phase extraction (SPE). Linearity in plasma was obtained over the concentration range 10~3000 pg/mL and lower limit of quantification (LLOQ) was identifiable and reproducible at 10 pg/mL. The intra- and inter-day precision values were below 9% and the accuracy was ranged from 93.81% to 102.02% at all four quality control samples. The method was has been successfully applied for routine assay to support pharmacokinetic study of misoprostol acid in human plasma after an oral administration of 0.4 mg misoprostol.

Carbon Monoxide Dispersion in an Urban Area Simulated by a CFD Model Coupled to the WRF-Chem Model (WRF-Chem 모델과 결합된 CFD 모델을 활용한 도시 지역의 일산화탄소 확산 연구)

  • Kwon, A-Rum;Park, Soo-Jin;Kang, Geon;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
    • /
    • v.36 no.5_1
    • /
    • pp.679-692
    • /
    • 2020
  • We coupled a CFD model to the WRF-Chem model (WRF-CFD model) and investigated the characteristics of flows and carbon monoxide (CO) distributions in a building-congested district. We validated the simulated results against the measured wind speeds, wind directions, and CO concentrations. The WRF-Chem model simulated the winds from southwesterly to southeasterly, overestimating the measured wind speeds. The statistical validation showed that the WRF-CFD model simulated the measured wind speeds more realistically than the WRF-Chem model. The WRF-Chem model significantly underestimated the measured CO concentrations, and the WRF-CFD model improved the CO concentration prediction. Based on the statistical validation results, the WRF-CFD model improved the performance in predicting the CO concentrations by taking complicatedly distributed buildings and mobiles sources of CO into account. At 04 KST on May 22, there was a downdraft around the AQMS, and airflow with a relatively low CO concentration was advected from the upper layer. Resultantly, the CO concentration was lower at the AQMS than the surrounding area. At 15 KST on May 22, there was an updraft around the AQMS. This resulted in a slightly higher CO concentration than the surroundings. The WRF-CFD model transported CO emitted from the mobile sources to the AQMS measurement altitude, well reproducing the measured CO concentration. At 18 KST on May 22, the WRF-CFD model simulated high CO concentrations because of high CO emission, broad updraft area, and an increase in turbulent diffusion cause by wind-shear increase near the ground.

Various Partial Charge Schemes on 3D-QSAR Models for P-gp Inhibiting Adamantyl Derivatives

  • Gadhe, Changdev G.;Madhavan, Thirumurthy;Kothandan, Gugan;Lee, Tae-Bum;Lee, Kyeong;Cho, Seung-Joo
    • Bulletin of the Korean Chemical Society
    • /
    • v.32 no.5
    • /
    • pp.1604-1612
    • /
    • 2011
  • We developed three-dimensional quantitative structure activity relationship (3D-QASR) models for 17 adamantyl derivatives as P-glycoprotein (P-gp) inhibitors. Eighteen different partial charge calculation methods were tested to check the feasibility of the 3D-QSAR models. Best predictive comparative molecular field analysis (CoMFA) model was obtained with the Austin Model 1-Bond Charge Correction (AM1-BCC) atomic charge. The 3D-QSAR models were derived with CoMFA and comparative molecular similarity indices analysis (CoMSIA). The final CoMFA model ($q^2$ = 0.764, $r^2$ = 0.988) was calculated with an AM1-BCC charge and electrostatic parameter, whereas the CoMSIA model ($q^2$ = 0.655, $r^2$ = 0.964) was derived with an AM1-BCC charge and combined steric, electrostatic, hydrophobic and HB-acceptor parameters. Leave-five-out (LFO) cross-validation was also performed, which yielded good correlation coefficient for both CoMFA (0.801) and CoMSIA (0.656) models. Robustness of the developed models was checked further with 1000 run bootstrapping analyses, which gave an acceptable correlation coefficient for CoMFA (BS-$r^2$ = 0.997, BS-SD = 0.003) and CoMSIA (BS-$r^2$ = 0.996, BS-SD = 0.018).

Assay Validation of Lansoprazole in Human Plasma

  • Lim, Yoon-Young;Woo, Jong-Soo;Kim, Chong-Kook
    • Proceedings of the PSK Conference
    • /
    • 2002.10a
    • /
    • pp.395.3-396
    • /
    • 2002
  • A simple, rapid and reliable high performance liquid chromatography (HPLC) method has been developed for the measurement of lansoprazole in human plasma, and the application of pharmacokinetic study has been evaluated. Omeprazole was used as an internal standard. After adding methyl tert-butyl ether, samples were stored at -7$0^{\circ}C$. The extracts were easily obtained only with pouring the organic phase. The mobile phase was prepared using acetonitrile and water at the volume ratio of 38:62. (omitted)

  • PDF

Co-rotational Plane Beam-Dynamic Tip Load를 이용한 Drone Single Arm 최적 설계

  • Park, Seon-Hu;Lee, Sang-Gu;Sin, Sang-Jun
    • Proceeding of EDISON Challenge
    • /
    • 2017.03a
    • /
    • pp.290-303
    • /
    • 2017
  • This paper aims to build a drone platform based on an optimum design of its single arm. We assumed its single arm as a cantilevered beam with a tip mass. Based on the numerical optimization theory, we conducted validation and optimization of a new design by comparing the results with the similar ones obtained by ANSYS. Finally, this design is reflected in the control simulation, and the requirement of an optimum structural design considering the resonance situation is demonstrated.

  • PDF

JAXA TechCLEAN Project

  • Futamura, Hisao;Hayashi, Shigeru
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2008.03a
    • /
    • pp.628-637
    • /
    • 2008
  • The JAXA's TechCLEAN project(2003-present) is summarized, with the interim technical achievements. TechCLEAN is collateral program with the NEDO engine project to accelerate R&D work of small passenger aircraft engine as well as to develop innovative environment technologies applicable to the future improvements. In the project NOx reduction, CO2 reduction and noise reduction are targeted. Component level researches and system demonstrator validation are planned with test facility renovation and demonstration base engines.

  • PDF

Combinatorial Library and Chemogenomics Approach: Discovery of Protein Secondary Structure Mimetic Small Molecule Inhibitors of Tryptase and Ref-l for Asthma

  • Moon, Sung-Hwan
    • Proceedings of the PSK Conference
    • /
    • 2003.10a
    • /
    • pp.92-92
    • /
    • 2003
  • The drug discovery landscape is changing rapidly in the post-genomic era. Mapping of the human genome has led to an abundance of potential drug targets. Drug discovery times and costs can be significantly reduced by developing methods for high throughput target identification/ validation, multiplexed assay development and high efficient combinatorial chemistry. (omitted)

  • PDF

Estimation of deformation modulus for rock mass using stress distribution under ground in Large Plate Load Test (대형평판재하시험의 지중응력 측정결과를 이용한 연암의 변형계수 산정)

  • Park, Won-Tae;Lee, Min-Hee;Choi, Yong-Kyu;Kim, Seok-Chan;Kim, Jung-Hwan
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.09a
    • /
    • pp.539-545
    • /
    • 2010
  • The field plate test has a good potential for determining since it measures both plate pressure and settlement. The deformation modulus of rock mass is differently measured for status of structures. The values of deformation modulus are obtained from laboratory test (uniaxial and triaxial test) and field test (pressuremeter test). Plate load test should be conducted by different loading plate sizes for geological structure of rock mass and scale of structures. In this paper, large plate load tests were performed to predict of structure's behavior and evaluate the ultimate bearing capacity of the foundation on soft rock. Simultaneously, deformation modulus of rock mass was estimated by back analysis of stresses measured in field test under rock mass. Finally, we verified the validation of deformation modulus of rock mass through result of large plate load test and numerical simulation.

  • PDF

Comparative Molecular Field Analyses (CoMFA) on the Mela-nogenesis Inhibitory Activities of Alkyl-3,4-dihydroxybenzoyl Derivatives.

  • Kim, Sang-Jin;Sung, Nack-Do;Lee, Tack-Hyuck
    • Proceedings of the SCSK Conference
    • /
    • 2003.09a
    • /
    • pp.225-231
    • /
    • 2003
  • To search and development a new material with superior melanogenesis inhibitory activity, the bioactivities (obs. pl$_{50}$) of alkyl-3,4-dihydroxybenzoyl esters and N-alkyl-3,4-dihydroxybenz-oyl amides as substrate molecules were measured in mouse melanoma cells. And also, we have studied that 3-D QSARs (3 dimensional Quantitative Structure-Activity Relationships) between molecular interaction field of substrates and the bioactivities were analyzed using CoMFA (Comparative Molecular Field Analyses) method. When cross-validation value (q$^2$) is 0.68 at 3 components, the Pearson correlation coefficient ($r^2$) is 0.900. From the basis on the findings, the model was appeared by the contour map such as steric field and electrostatic field relationships between quantitative structure and the bioactivity of the various substrate derivatives. Measured bioactivities (obs. pl$_{50}$) of unknown compounds are very similar to predicted activity (pred. pl$_{50}$) according to the CoMFA model. As the results of prediction, we could conclude that the bioactivities were increased by creation of R$_1$ substitution of 5,5-dime-thylhexoxy, 6,6-dimethylheptyl, 1-amino-6,6-dimethylheptyl group etc and R$_2$ substitution of hydroxy, methyl, methoxy group etc.p etc.

  • PDF