• Korean Journal of Microbiology
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• v.30 no.2
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• pp.78-82
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• 1992

The dikaryon of Trimorphonzycc,.~ papilioncicc.ous, one of basidiornycetous yeast needed thiamine as a growth factor and required relatively simple nutrient components. This organism grem best at 25$^{\circ}$C. anci showed broad pH range (pH 4.0-7.0). It was groM,n in liquid minimal media with various carbon sources and they could be classilied into 3 groups as follows. Glucose. fructose. mannose, sucrose and xylose (A gi.oup) supportecl good growth (>OD 0.8), and showed poor laccase activity (less than 1.5 u'mg protein). Galactose and gluconate (B group) showed moderate growth (01) 0.3-0.6). and hail moderatc crlzyrne activity (4-6u). Arabinosc. lactose. maltose ant1 pyruvate (C 5roup) showed poor growth (OD 0.1-0.2). and showed high enzyme activity (higher than 8 u). Kibosc, acetate. citrate. lactate and oxaloacetate showed no growth. When the yeast was grown in a medium which had two carbon sources (glucose and arabinose). laccase was regul;~tecl by the cutahoiitc repression.

• Journal of the Korean Society for Nondestructive Testing
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• v.37 no.2
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• pp.91-98
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• 2017

Recently, composite materials have been mainly used in the main wings, ailerons, and fuselages of aircraft and rotor blades of helicopters. Composite materials used in rapid moving structures are subject to impact by hail, lightning, and bird strike. Such an impact can destroy fiber tissues in the composite materials as well as deform the composite materials, resulting in various problems such as weakened rigidity of the composite structure and penetration of water into tiny cracks. In this study, experiments were conducted using a 2 kW halogen lamp which is most frequently used as a light source, a 2 kW near-infrared lamp, which is used for heating to a high temperature, and a 6 kW xenon flash lamp which emits a large amount of energy for a moment. CFRP composite sandwich panels using Nomex honeycomb core were used as the specimens. Experiments were carried out under impact damages of 1, 4 and 8 J. It was found that the detection of defects was fast when the xenon flash lamp was used. The detection of damaged regions was excellent when the halogen lamp was used. Furthermore, the near-infrared lamp is an effective technology for showing the surface of a test object.

• English Language & Literature Teaching
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• no.5
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• pp.259-272
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• 1999

The real nature of the west wind in Shelley's Ode to the West Wind is the divine providence which influences all things in this world- that is, whether they are on land, in the sky, or in the sea. The divine providence is the manifestation of something beyond the present and tangibel object. In the first stanza, the real nature of the west wind in this poem is the wild wind, the breath of Autumn's being, the unseen presence, the azure sister of the Spring, a Destroyer, a Preserver, the winged seed, a creator, a philosopher, a poet, Shelley, and the wild spirit moving everywhere. In the second stanza, the real nature of the west wind in this poem is cloud, the angel of rain and lightning, fierce Maenad, the approaching storm, the congregated might, the black rain, the fire, hail, solid atmosphere, the tremendous power of revolutionary change, and the power that influences all things in the sky. In the third stanza, the real nature of the west wind in this poem is the voice that makes the oozy woods which wear the sapless foliage of the Atlantic, and the power makes the blue Mediterranean wake from his summer dream. the fit medium of expression which Shelley's soul was seeking for, Shelley's passion, Shelley's partner, Shelley's co-worker, and a strong presence which influences in the sea. In the fourth stanza, the real nature of the west wind in this poem is the mightest presence, the power, the strength, the free presence, the uncontrollable, the wanderer over heaven, a vision, the tameless, the swift, the proud and the God who can save Shelley form the heavy weight of hours and lift Shelley as a wave a leaf, a cloud. In the fifth stanza, the real nature of the west wind in this poem is the mighty harmony, the fierce Spirit, Shelley's spirit, the impetuous spirit, incanation of this verse, spark, the trumpet of a prophecy, the Providence which can make the Winter depart and call Spring, and the prophet. To conclude, the real nature of the west wind in this poem is Shelley's accumulated insight that he visulize his impulse of revolutionary thought.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.565-578
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• 1997

Clouds are usually formed by adiabatic cooling through ascending currents, radiation cooling or a mixture of warm air and cold one. Ascending currents are caused by covection currents, or they are accompanied with fronts. Thus clouds are formed through various kinds of causes and procedures. So they are various in height and shape. Form of clouds was classified on the basis of the thecriteria that L. Howard proposed in 1803. He distinguished three simple, fundamental classes-Cirrus, Cumulus, Stratus-from which the others were derived by trasition or association. And they are subdivided into 10 genera according to their height and shape. Most of the clouds are subdivided into the detailed kinds to the characteristics such as appearance or intensity of convection current. Sometimes completly different shape of cloud can be developed out of the 'mother-cloud'. In korea, the stratocumulus, altostratus and cirrus clouds frequently appear. Generally we are likely to have rain or snow from the stratus cloud forms(As, St, Sc) and rain shower or hail from the cumulus forms(Ac, Cu, Cb).

• Journal of Korean Society for Geospatial Information Science
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• v.15 no.4
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• pp.11-20
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• 2007

Most natural disasters in Korea are caused by meteorological natural phenomena, which include storms, heavy rains, heavy snow, hail, tidal waves, and earthquakes. Rainfall is the most frequent cause of disasters and accounts for about 80% of all disasters. Particularly in recent years, Korea has seen annual occurrences of natural disasters associated with landslides (slope and retaining wall collapse and burying) due to meteorological causes from the increasing intensity of heavy rains including local heavy rainfalls. In Korea, it is critical to analyze the characteristics of landslides according to rainfall characteristics and to take necessary and proper measures for them. This study assessed the possibility of landslides in the Gangwon region with a geographic information system by taking into account the inducer factors of landslides and the maximum continuous rainfall of each area. It also analyzed areas susceptible to landslides and checked the distribution of landslide-prone areas by considering the rainfall characteristics of those areas.

• Journal of mucopolysaccharidosis and rare diseases
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• v.2 no.2
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• pp.43-45
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• 2016

Whole body energy balance is achieved through the coordinated regulation of energy intake and energy expenditure in various tissues including liver, muscle and adipose tissues. A positive energy imbalance by excessive energy intake or insufficient energy expenditure results in obesity and related metabolic diseases. Although there have been many obesity treatment trials aimed at the reduction of energy intake, these strategies have achieved only limited success because of their associated adverse effects. Serotonin is among those traditional pharmacological targets for anti-obesity treatment because central 5-HT functions as an anorexigenic neurotransmitter in the brain. Thus, there have been many trials aimed at increasing the activity of 5-HT in the central nervous system, and some of the developed methods are already used in the clinical setting as anti-obesity drugs. However, recent studies suggest the new functions of peripheral serotonin in energy homeostasis ranging from the endocrine regulation by gut-derived serotonin to the autocrine/paracrine regulation by adipocyte-derived serotonin. Pharmacological inhibition of 5-HT synthesis leads to inhibition of lipogenesis in epididymal white adipose tissue (WAT), induction of browning in inguinal WAT and activation of adaptive thermogenesis in brown adipose tissue (BAT). Fat specific Tph1 knock-out (Tph1 FKO) mice exhibit similar phenotypes as mice with pharmacological inhibition of 5-HT synthesis, suggesting the localized effects of 5-HT in adipose tissues. In addition, Htr3a KO mice exhibit increased energy expenditure in BAT and Htr2a KO mice exhibit the decreased lipid accumulation in WAT. These data suggest the clinical significance of the peripheral serotonergic system as a new therapeutic target for anti-obesity treatment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.11
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• pp.1492-1499
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• 2020

A weather radar system generally shows the weather phenomena related with rainfall and wind velocity. These systems are usually very helpful to monitor the relatively high altitude weather situation for the wide and long range area. However, since the weather hazards due to the strong hail and heavy rainfall occurring locally are observed frequently in recent days, it is important to detect these wether phenomena. For this purpose, it is necessary to detect the fast varying low altitude weather conditions. In this environment, the effect of surface clutter is more evident and the antenna dwell time is much shorter. Therefore, the conventional Doppler spectrum estimation method may cause serious problems. In this paper, the AR(autoregressive) Doppler spectrum estimation methods were applied to solve these problems and the results were analyzed. Applied methods show that improved Doppler spectra can be obtained comparing with the conventional FFT(Fast Fourier Transform) method.

• Atmosphere
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• v.31 no.5
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• pp.489-510
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• 2021

In this paper, we propose an algorithm for detecting convective initiation (CI) using GEO-KOMPSAT-2A/advanced meteorological imager data. The algorithm identifies clouds that are likely to grow into convective clouds with radar reflectivity greater than 35 dBZ within the next two hours. This algorithm is developed using statistical and qualitative analysis of cloud characteristics, such as atmospheric instability, cloud top height, and phase, for convective clouds that occurred on the Korean Peninsula from June to September 2019. The CI algorithm consists of four steps: 1) convective cloud mask, 2) cloud object clustering and tracking, 3) interest field tests, and 4) post-processing tests to remove non-convective objects. Validation, performed using 14 CI events that occurred in the summer of 2020 in Korean Peninsula, shows a total probability of detection of 0.89, false-alarm ratio of 0.46, and mean lead-time of 39 minutes. This algorithm can be useful warnings of rapidly developing convective clouds in future by providing information about CI that is otherwise difficult to predict from radar or a numerical prediction model. This CI information will be provided in short-term forecasts to help predict severe weather events such as localized torrential rainfall and hail.

• Current Optics and Photonics
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• v.7 no.6
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• pp.721-731
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• 2023

This paper studies various roughness parameters, besides waviness, texture, and nonlinear parameters of Bismarck brown Y (BBY)-doped Poly(methyl methacrylate) (PMMA) films based on the computed values of optical limiting (OL) threshold power and nonlinear refractive index. The films' morphology, grain size, and absorption spectra were investigated using atomic force microscopy in conjunction with ultraviolet-visible (UV-Vis) spectrophotometer. The particle size of the films ranged between 4.11-4.51 mm and polymer films showed good homogeneity and medium roughness, ranging from 1.11-4.58 mm. A polymer film's third-order nonlinear optical features were carried out using the Z-scan methodology. The measurements were obtained by a continuous wave produced from a solid-state laser with a 532 nm wavelength. According to the results, BBY has a nonlinear refractive index of 10^-6 cm²/W that is significantly negative and nonlinear. The optical limiting thresholds are roughly 10.29, 13.52, and 18.71 mW, respectively. The shift of nonlinear optical features with the film's concentration was found throughout the experiment Additionally, we found that the polymer samples have outstanding capabilities for restricting the amount of optical power that may be transmitted through them. We propose that these films have the potential to be used in a wide variety of optoelectronic applications, including optical photodetectors and optical switching.

• Journal of the Korean earth science society
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• v.28 no.7
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• pp.857-870
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• 2007

The structure and evolution of a thunderstorm outflow in two dimensions with no environmental wind are investigated using a cloud-resolving model with explicit liquid-ice phase microphysical processes (ARPS: Advanced Regional Prediction System). The turbulence structure of the outflow is explicitly resolved with a high-resolution grid size of 50m. The simulated single-cell storm and its associated Kelvin-Helmholtz (KH) billows are found to have the lift stages of development maturity, and decay. The secondary pulsation and splitting of convective cells resulted from interactions between cloud dynamics and microphysics are observed. The cooled downdrafts caused by the evaporation of rain and hail in the relatively dry lower atmosphere result in thunderstorm cold-air outflow. The outflow head propagates with almost constant speed. The KH billows formed by the KH instability cause turbulence mixing from the top of the outflow and control the structure of the outflow. Ihe KH billows are initiated at the outflow head, and pow and decay as moving rearward relative to the gust front. The numerical simulation results of the ratio of the horizontal wavelength of the fastest growing perturbation to the critical shear-layer depth and the ratio of the horizontal wavelength of the billow to its maximum amplitude are matched well with the results of other studies.