• Bulletin of the Korean Space Science Society
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• 2008.10a
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• pp.22.2-22.2
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• 2008

Radio and X-ray observations of radio lobes in galaxy clusters indicate large energies stored in the magnetic fields in the radio lobes. These magnetic fields are undoubtedly produced and amplified by the accretion onto the central supermassive black hole. I review recent progress and remaining problems in our understanding of the ways how these magnetic fields can be produced and amplified in the accretion disks and what can be the limiting strength of the magnetic field. The major remaining issue is how ordered magnetic spirals (or jets) can emerge from the turbulent small scale magnetic fields produced by MRI. Another issue is the ratio of the axial to the azimuthal magnetic field in jets.

• Interaction and multiscale mechanics
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• v.3 no.4
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• pp.373-387
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• 2010

This study is intended to assess low frequency sound radiated from a viaduct under normal traffic. The bridge comprises steel box girders and wide cantilever decks on which vehicles pass. The low frequency sound and the acceleration response of the bridge under normal traffic are measured to investigate how bridge vibrations affect the low frequency sound observed near the bridge. Observations demonstrate that strong relationships exist between frequency characteristic of bridge's acceleration response and the sound pressure level of low frequency sound. A noteworthy point is that the dynamic feature of the sound pressure level is mostly affected by dynamic feature of the span locating near the observation point.

• Tuberculosis and Respiratory Diseases
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• v.75 no.2
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• pp.47-51
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• 2013

Interstitial lung diseases are heterogeneous entities with diverse clinical presentations. Among them, idiopathic pulmonary fibrosis and connective tissue disease-associated interstitial lung disease are specific categories that pulmonologists are most likely to encounter in the clinical field. Despite the accumulated data from extensive clinical trial and observations, we continue to have many issues which need to be resolved in this field. In this update, we present the review of several articles regarding the clinical presentation, prognosis and treatment of patients with idiopathic pulmonary fibrosis or connective tissue disease-associated interstitial lung disease.

• Journal of Environmental Science International
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• v.5 no.2
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• pp.103-112
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• 1996

Observational date is integral in our understanding of present climate, its natural variability and any cnange roue to anturopogenic effects. This study incorporates a brief overview of sampling requirements using data from the first ISLSCP Field Experiment (FIFE) in 1987, which was a multi-disciplinary field experiment over a 15km grid in Konza Prairie, USA. Sampling strategies were designed for precipitation and soil moisture measurements and also detecting land cover type. It was concludes that up to 8 raingages would be needed for valuable precipitation measurements covering the whole FIFE catchment, but only one soil moisture station. Results show that as new gages or station are added to the catchment then the sampling error is reduced, but the Improvement in error performance is less as the number of gages or stations increases. Sampling from remoteiy sensed instruments shows different results. It can be seen that the sampling error at 1arger resolution sizes are small due to competing error contribution from both commission and omission error.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.85-86
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• 1996

The imaging spectroscopic observations of the Magellanic irregular galaxy NGC 4449 were made to show the detailed kinematic structure of the galaxy. Many filamentary structures and Several bubble-like structures are recognized in a 3D data cube of H$\alpha$ emission line. Velocity field shows the kpc-scale mosaic structure and counter- rotation of ionized gas.

• ALGAE
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• v.27 no.1
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• pp.43-54
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• 2012

A mathematical model of the commercial harvest of Palmaria palmata (Dulse) is presented based on a logistic model and field data collected on Digby Neck, Nova Scotia from 14 harvested shores during May to August, 2010. Field observations used to estimate model parameters included cover of Dulse before and after harvest from Dulse dominated boulders for which surface area was estimated, and from which fresh biomass of harvested Dulse was weighed. Over all the surveys the average harvest fraction was about 50%, and the total resource was about $1,600g\;m^{-2}$. With growth rates in excess of 4% per day and a 50% harvest of the standing crop each month, the model suggests that the Dulse resource is sustainable at current harvest levels.

• Wind and Structures
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• v.19 no.5
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• pp.541-563
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• 2014

This paper investigates the topographic effects on wind characteristics over hilly terrain, based on wind data recorded at a number of meteorological stations in or near complex terrain. The multiply data sources allow a more detailed investigation of the flow field than is normally possible. Vertical profiles of mean and turbulent wind components from a Sodar profiler were presented and then modeled as functions of height and wind speed. The correlations between longitudinal and vertical wind components were discussed. The phenomena of flow separation and generation of vortices were observed. The distance-dependence of the topographic effects on gust factors was revealed subsequently. Furthermore, the canyon effect was identified and discussed based on the observations of wind at a saddle point between two mountain peaks. This study aims to further understanding of the characteristics of surface wind over rugged terrain. The presented results are expected to be useful for structural design, prevention of pollutant dispersion, and validation of CFD (computational fluid dynamics) models or techniques over complex terrains.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.85.1-85.1
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• 2011

The magnetic field at the surface of the Sun is concentrated in magnetic features that often have spatial extents of 100 km or less. The study of the fine scale structure of the Sun's magnetic field has been hampered by the limited spatial resolution of the available observations. This has recently changed thanks to various new high-resolution facilities, among them the SUNRISE observatory, built around the largest solar telescope to leave the ground, and containing two science instruments. SUNRISE successfully had its first long-duration science flight on a stratospheric balloon in June 2009 and a host of scientific results have been obtained from the data. After a brief introduction to the Sunrise mission, an overview of selected results obtained so far will be given. A reflight at higher solar activity is currently being prepared.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.69.2-69.2
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• 2014

To estimate free magnetic energy stored in an active region is a key to the quantitative prediction of activity observed on the Sun. This energy is defined as an excess over the potential energy that is the lowest energy taken by a magnetic structure formed in the solar atmosphere including the solar corona. It is, however still difficult to derive the configuration of a coronal magnetic field only by observations, so we have to use some observable quantity to estimate free magnetic energy. Recently, by performing a coordinated series of three-dimensional magnetohydrodynamic simulations of an emerging flux tube that transfers intense magnetic flux to the solar atmosphere we have found an universal power-law relation between free magnetic energy and emerged magnetic flux, the latter of which is a possibly observed quantity. We further investigate what causes this relation through a comparison with a model of linear force-free field.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.525-527
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• 2003

This paper presents a collection of a number of observations made on 4 bundled conductor transmission lines concerning the behaviour of conductors under the effect of natural winds. Namely in order to know the wind-induced vibration status and study wind-induced vibrations have been recorded and analyzed form the real transmission lines. By the field observation and analysis results, subspan oscillations among the wind-induced vibrations is known to be the main type of the vibrations. And some common characteristics of the observation sites, which have had high maintenance rate, can be found from the data also. It is considered that the main results described in this paper will be useful data and be used in controlling the subspan oscillations and protecting the conductors.