• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.65-65
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• 2011

Early-type galaxies represent the end point of galaxy evolution and, despite pervasive residual star formation, are generally considered "red and dead", that is composed exclusively of old stars with no star formation. Here, their molecular gas content is constrained and discussed in relation to their evolution, supporting the continuing importance of minor mergers and/or cold gas accretion. First, as part of the Atlas3D survey, the first complete, large, volume-limited survey of CO in normal early-type galaxies is presented. At least of 23% of local early-types possess a substantial amount of molecular gas, the necessary ingredient for star formation, independent of mass and environment but dependent on the specific stellar angular momentum. Second, using CO synthesis imaging, the extent of the molecular gas is constrained and a variety of morphologies is revealed. The kinematics of the molecular gas and stars are often misaligned, implying an external gas origin in over a third of all systems, more than half in the field, while external gas accretion must be shot down in clusters. Third, many objects appear to be in the process of forming regular kpc-size decoupled disks, and a star formation sequence can be sketched by piecing together multi-wavelength information on the molecular gas, current star formation, and young stars. Fourth, early-type galaxies do not seem to systematically obey all our usual prejudices regarding star formation (e.g. Schmidt-Kennicutt law, far infrared-radio continuum correlation), suggesting a greater diversity in star formation processes than observed in disk galaxies and the possibility of "morphological quenching". Lastly, a first step toward constraining the physical properties of the molecular gas is taken, by modeling the line ratios of density- and opacity-sensitive molecules in a few objects. Taken together, these observations argue for the continuing importance of (minor) mergers and cold gas accretion in local early-types, and they provide a much greater understanding of the gas cycle in the galaxies harbouring most of the stellar mass. In the future, better dust masses and dust-to-gas mass ratios from Herschel should allow to place entirely independent constraints on the gas supply, while spatially-resolved high-density molecular gas tracers observed with ALMA will probe the interstellar medium and star formation laws locally in a regime entirely different from that normally probed in spiral galaxies.

• Molecules and Cells
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• v.26 no.1
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• pp.61-66
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• 2008

Cyclic AMP receptor protein (CRP) is allosterically activated by cAMP and functions as a global transcription regulator in enteric bacteria. Structural information on CRP in the absence of cAMP (apo-CRP) is essential to fully understand its allosteric behavior. In this study we demonstrated interdomain interactions in apo-CRP, using a comparative thermodynamic approach to the intact protein and its isolated domains, which were prepared either by limited proteolysis or using recombinant DNA. Thermal denaturation of the intact apo-CRP, monitored by differential scanning calorimetry, revealed an apparently single cooperative transition with a slight asymmetry. Combined with circular dichroism and fluorescence analysis, the thermal denaturation of apo-CRP could be interpreted as a coupled process involving two individual transitions, each attributable to a structural domain. When isolated individually, both of the domains exhibited significantly altered thermal behavior, thus pointing to the existence of non-covalent interdomain interactions in the intact apo-CRP. These observations suggest that the allosteric conformational change of CRP upon binding to cAMP is achieved by perturbing or modifying pre-existing interdomain interactions. They also underline the effectiveness of a comparative approach using calorimetric and structural probes for studying the thermodynamics of a protein.

• CELLMED
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• v.2 no.2
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• pp.17.1-17.5
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• 2012

Ayurveda is a nearly 3000 years old traditional medical system of India. Most of the time, people turn to ayurvedic physicians in desperate conditions. Here clinical practices of Ayurveda were initially found effective in the management of migraine among few patients. Later, it was developed as an ayurvedic treatment protocol (ATP) which consists of four herbo-mineral formulations (HMF), three meals and three snacks in a day with eight hours sleep at night. ATP brought significant relief in reducing the frequency, intensity of pain and associated symptoms in the migraine patients. IHS diagnostic criteria was followed to establish the diagnosis of migraine and uniform ATP was prescribed to each patient who were primarily treated by the ayurvedic physicians at their respective clinics. Such observations were presented at appropriate international forums. In an effort to validate the above, the present study carries the details of nine migraine patients who were first diagnosed and treated for migraine by a leading headache expert at Mumbai in India and were then referred to receive ATP. A total number of nine subjects volunteered to this program. Out of those, seven subjects completed 120 days of ATP. Five subjects reported significant improvement in overall symptoms of migraine. All subjects were followed up periodically for four years. No Grade II side effects were observed in any treated case. HMF has also been proved to be safe in experimental studies. Further pharmacological and randomized controlled clinical studies are in progress at the respective departments of a premier medical institute in India.

• Smart Structures and Systems
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• v.17 no.6
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• pp.995-1015
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• 2016

In the design and condition assessment of bridges, it is usually necessary to take into consideration the extreme conditions which are not expected to occur within a short time period and thus require an extrapolation from observations of limited duration. Long-term structural health monitoring (SHM) provides a rich database to evaluate the extreme conditions. This paper focuses on the extrapolation of extreme traffic load effects on bridges using long-term monitoring data of structural strain. The suspension Tsing Ma Bridge (TMB), which carries both highway and railway traffic and is instrumented with a long-term SHM system, is taken as a testbed for the present study. Two popular extreme value extrapolation methods: the block maxima approach and the peaks-over-threshold approach, are employed to extrapolate the extreme stresses induced by highway traffic and railway traffic, respectively. Characteristic values of the extreme stresses with a return period of 120 years (the design life of the bridge) obtained by the two methods are compared. It is found that the extrapolated extreme stresses are robust to the extrapolation technique. It may owe to the richness and good quality of the long-term strain data acquired. These characteristic extremes are also compared with the design values and found to be much smaller than the design values, indicating conservative design values of traffic loading and a safe traffic-loading condition of the bridge. The results of this study can be used as a reference for the design and condition assessment of similar bridges carrying heavy traffic, analogous to the TMB.

• Structural Engineering and Mechanics
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• v.39 no.2
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• pp.241-266
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• 2011

The Self Compacting Concrete, SCC is the new generation type of concrete which is not needed to be compacted by vibrator and it will be compacted by its own weight. Since SCC is a new innovation and also the high strength self compacting concrete, HSSCC behavior is like a brittle material, therefore, understanding the strength effect on the serviceability performance of reinforced self compacting concretes is critical. For this aim, first the normal and high strength self compacting concrete, NSSCC and HSSCC was designed. Then, the serviceability performance of reinforced connections consisting of NSSCC and HSSCC were investigated. Twelve reinforced concrete connections (L = 3 m, b = 0.15 m, h = 0.3 m) were simulated, by this concretes, the maximum and minimum reinforcement ratios ${\rho}$ and ${\rho}^{\prime}$ (percentage of tensile and compressive steel reinforcement) are in accordance with the provision of the ACI-05 for conventional RC structures. This study was limited to the case of bending without axial load, utilizing simple connections loaded at mid span through a stub (b = 0.15 m, h = 0.3 m, L = 0.3 m) to simulate a beam-column connection. During the test, concrete and steel strains, deflections and crack widths were measured at different locations along each member. Based on the experimental readings and observations, the cracked moment of inertia ($I_{cr}$) of members was determined and the results were compared with some selective theoretical methods. Also, the flexural crack widths of the members were measured and the applicability for conventional vibrated concrete, as for ACI, BS and CSA code, was verified for SCCs members tested. A comparison between two Codes (ACI and CSA) for the theoretical values cracking moment is indicate that, irrespective of the concrete strength, for the specimens reported, the prediction values of two codes are almost equale. The experimental cracked moment of inertia $(I_{cr})_{\exp}$ is lower than its theoretical $(I_{cr})_{th}$ values, and therefore theoretically it is overestimated. Also, a general conclusion is that, by increasing the percentage of ${\rho}$, the value of $I_{cr}$ is increased.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.1
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• pp.27.2-27.2
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• 2011

The Kepler(NASA) and CoRoT(ESA) space telescopes are surveying thousands of exoplanet for finding Earth-like exoplanets with similar environments of the Earth. Then the TPF(NASA), DARWIN(ESA) and many large-aperture ground telescopes have plan for spectroscopic observations of these earth-like exoplanets in next decades. Now, it has been started to simulate the disk averaged spectra of the earthlike exoplanets for comparing the observed spectra and suggesting solutions of environment of these planets. Previous research, the simulations are based on radiative transfer method, but these are limited by optical models of Earth system and instruments. We introduce a new simulation method, IRT(Integrated Ray Tracing) to overcome limitations of previous method. The 3 components are defined in IRT; 1)Sun model, 2)Earth system model (Atmosphere, Land and Ocean), 3)Instrument model. The ray tracing in IRT is simulated in composed 3D real scale space from inside the sun model to the detector of instrument. The Sun model has hemisphere structure with Lambertian scattering optical model. Atmosphere is composed of 16 distributed structures and each optical model includes BSDF with using 6SV radiative transfer code. Coastline and 5 kinds of vegetation distribution data are used to land model structure, and its non-Lambertian scattering optical model is defined with the semi-empirical "parametric kernel method" used for MODIS(NASA) and POLDER(CNES) missions. The ocean model includes sea ice cap structure with the monthly sea ice area variation, and sea water optical model which is considering non-lambertian sun-glint scattering. Computation of spectral imaging and radiative transfer performance of Earth system model is tested with hypothetical space instrument in IRT model. Then we calculated the disk averaged spectra of the Earth system model in IRT computation model for 8 cases; 4 viewing orientation cases with full illuminated phase, and 4 illuminated phase cases in a viewing orientation. Finally the DAS results are compared with previous researching results of radiative transfer method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.395-400
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• 2006

Among the various error sources in positioning and navigation, the paper focuses on the modeling and prediction of receiver clock bias and then tries to achieve positioning based on simulated and predicted clock bias. With the SA off, it is possible to model receiver clock bias more accurately. We selected several types of GNSS receivers for test using ARMA model. To facilitate prediction with short and limited sample pseudorange observations, AR and ARMA are compared, and the improved AR model is presented to model and predict receiver clock bias based on previous solutions. Our work extends to clock bias prediction and positioning based on predicted clock bias using only 3 satellites that is usually the case under urban canyon situation. In contrast to previous experiences, we find that a receiver clock bias can be well modeled using adopted ARMA model. Test has been done on various types of GNSS receivers to show the validation of developed model. To further develop this work, we compare solution conditions in terms of DOP values when point positioning is conducted using 3 satellites to simulate urban positioning environment. When condition allows, height component is derived from other ways and can be set as known values. Given this condition, location is possible using less than 2 GNSS satellites with fixed height. Solution condition is also discussed for this background using mode of constrained positioning. We finally suggest an effective predictive time span based on our test exploration under varied conditions.

• Applied Microscopy
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• v.34 no.2
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• pp.95-102
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• 2004

The TEM samples prepared by ion milling have the advantage that thin area can be obtained from almost any materials. However, it has the disadvantage that the amount of thin area can often be quite limited. For the cross-sectioned samples and grossly heterogeneous materials, the thickness of less than $0.1{\mu}m$ can be achieved by mechanical grinding and polishing (tripod polisher) and then the TEM samples may be ion-milled for final thinning or cleaning. These approaches were described in this paper. Examples of TEM observations were taken from cross-section samples of thin films on silicon and sapphire, from diffusion layers between $Mo_5Si_3\;and\;Mo_2B$, and from rapidly solidified 304 stainless steel powders embedded in electroplated copper.

• Journal of Soil and Groundwater Environment
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• v.7 no.1
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• pp.25-31
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• 2002

This study attempts to elucidate the possibility of treating landfill leachate by steelers' dust/${H_2}{O_2}$ system in a well-mixed batch reactor. Experiments were conducted to investigate the effects of operating variables such as pH, dust and ${H_2}{O_2}$ dosages and ${H_2}{O_2}$ injection method on the treatment efficiency, Contaminant concentrations were identified by TOC (Total Organic Carbon) analyzer. Experimental observations showed the possibility of steelers' dust as a catalytic reagent in the ${H_2}{O_2}$/dust system. The batch experiments showed that the optimal $H_2O$$_2$ and dust dosage, 20g/L dust. 2,000mg/L ${H_2}{O_2}$ removed about 75% of initial TOC concentration (250mg/1) within 60 min. And the TOC removal in the ${H_2}{O_2}$/dust system effectively proceeded only within a limited pH range of 3-4. The stealers' dust-catalyzed oxidative treatment of landfill leachate was more efficient compared with the $FeSO_2$catalyzed system (Fenton oxidation) for the removal rate and the cost.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.39-39
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• 2012

Data assimilation techniques have received growing attention due to their capability to improve prediction in various areas. Despite of their potentials, applicable software frameworks to probabilistic approaches and data assimilation are still limited because the most of hydrologic modelling software are based on a deterministic approach. In this study, we developed a hydrological modelling framework for sequential data assimilation, namely MPI-OHyMoS. MPI-OHyMoS allows user to develop his/her own element models and to easily build a total simulation system model for hydrological simulations. Unlike process-based modelling framework, this software framework benefits from its object-oriented feature to flexibly represent hydrological processes without any change of the main library. In this software framework, sequential data assimilation based on the particle filters is available for any hydrologic models considering various sources of uncertainty originated from input forcing, parameters and observations. The particle filters are a Bayesian learning process in which the propagation of all uncertainties is carried out by a suitable selection of randomly generated particles without any assumptions about the nature of the distributions. In MPI-OHyMoS, ensemble simulations are parallelized, which can take advantage of high performance computing (HPC) system. We applied this software framework for several catchments in Japan using a distributed hydrologic model. Uncertainty of model parameters and radar rainfall estimates is assessed simultaneously in sequential data assimilation.