• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.42.1-42.1
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• 2019

We observed 80 dense cores ($N(H_2)$ > $10^{22}cm^{-2}$) in the Orion molecular cloud complex which contains the Orion A (39 cores), B (26 cores), and ${\lambda}$ Orionis (15 cores) clouds. We investigate the behavior of the different molecular tracers and look for chemical variations of cores in the three clouds in order to systematically investigate the effects of stellar feedback. The most commonly detected molecular lines (with the detection rates higher than 50%) are $N_2H^+$, $HCO^+$, $H^{13}CO^+$, $C_2H$, HCN, and $H_2CO$. The detection rates of dense gas tracers, $N_2H^+$, $HCO^+$, $H^{13}CO^+$, and $C_2H$ show the lowest values in the ${\lambda}$ Orionis cloud. We find differences in the D/H ratio of $H_2CO$ and the $N_2H^+/HCO^+$ abundance ratios among the three clouds. Eight starless cores in the Orion A and B clouds exhibit high deuterium fractionations, larger than 0.10, while in the ${\lambda}$ Orionis cloud, no cores reveal the high ratio. These chemical properties could support that cores in the ${\lambda}$ Orionis cloud are affected by the photo-dissociation and external heating from the nearby H II region. An unexpected trend was found in the $[N_2H^+]/[HCO^+]$ ratio with a higher median value in the ${\lambda}$ Orionis cloud than in the Orion A/B clouds than; typically, the $[N_2H^+]/[HCO^+]$ ratio is lower in higher temperatures and lower column densities. This could be explained by a longer timescale in the prestellar stage in the ${\lambda}$ Orionis cloud, resulting in more abundant nitrogen-bearing molecules. In addition to these chemical differences, the kinematical difference was also found among the three clouds; the blue excess, which is an infall signature found in optically thick line profiles, is 0 in the ${\lambda}$ Orionis cloud while it is 0.11 and 0.16 in the Orion A and B clouds, respectively. This result could be another evidence of the negative feedback of active current star formation to the next generation of star formation.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.6
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• pp.1201-1208
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• 2020

A mass of seawater with similar properties in the ocean is called a water mass, and the front is a sea area where two masses of different properties meet. The gradient algorithm is a method of extracting where the sea water temperature pixel changes rapidly assuming that the slope is large, and the place with the large slope is assumed to be a front. This method is able to process large amounts of satellite data at once. Therefore, in this study, we tried to find the front lines in the sea area around the Korean Peninsula by using a gradient algorithm. The study data used gridded sea surface temperature satellite data. The resolution was 1/4°, and the monthly average data from January 1993 to December 2018 were used. There were major five fronts representatively, China Coastal Front, South Sea Coastal Front, Kuroshio Front/ Kuroshio Extension Front, Subpolar Front and the Subarctic Front. As a result of comparing the distribution of front by season, more types of front were distributed in winter and spring than in summer and autumn, and the distribution range was wider.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.5
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• pp.57-66
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• 2022

The Road Management Administration is cracking down on overloaded vehicles by installing low-speed or high-speed WIMs at toll gates and main lines on expressways. However, in recent years, the act of intelligently evading the overloaded-vehicle control system of the Road Management Administration by illegally manipulating the variable axle of an overloaded truck is increasing. In this manipulation, when entering the overloaded-vehicle checkpoint, all axles of the vehicle are lowered to pass normally, and when driving on the main road, the variable axle of the vehicle is illegally lifted with the axle load exceeding 10 tons alarmingly. Therefore, this study developed a technology to detect the state of the variable axle of a truck driving on the road using roadside camera images. In particular, this technology formed the basis for cracking down on overloaded vehicles by lifting the variable axle after entering the checkpoint and linking the vehicle with the account information of the checkpoint. Fundamentally, in this study, the tires of the vehicle were recognized using the Mask RCNN algorithm, the recognized tires were virtually arranged before and after the checkpoint, and the height difference of the vehicle was measured from the arrangement to determine whether the variable axle was lifted after the vehicle left the checkpoint.

• The Journal of Internal Korean Medicine
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• v.29 no.4
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• pp.1048-1060
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• 2008

Cirsii Japonici Herba(CJ) is a wild perennial herb found in many areas of Korea as well as China and Japan, which has been used to treat bleeding and inflammation. Silibinin is the main flavonoid extracted from milk thistle (Cirsii Japonici Herba). It exhibits potent antioxidant activity and anti-inflammatory effect. In this study, the effect of CJ and silibinin extract on lipopolysaccharide-induced inflammation was investigated using MTS assay, RT-PCR, western blot, and nitric oxide detection on mouse BV2 microglial cell lines. In the present results, CJ and silibinin extract suppressed nitric oxide production by inhibiting the lipopolysaccharide-stimulated enhancement of COX-2 and iNOS gene expression in BV2 cells. Moreover, CJ and silibinin also repressed some lipopolysaccharide-induced signaling molecules. Importantly, catalase-induced COX-2 and iNOS expression needed activations of $NF-{\kappa}B$, PI3K/Akt, and MAPK, which were important for the transcriptional up-regulation of COX-2 and iNOS. CJ and silibinin interaction on BV2 cells down-regulated $NF-{\kappa}B$-dependent proinflammatory cytokine (IL-2,IL-6) expression. They are involved in the regulation of inflammatory responses. These data shows that CJ and silibinin exerts anti-inflammatory and analgesic effects, probably by suppression of COX-2 and iNOS synthase expression in BV2 microglial cells.

• Geophysics and Geophysical Exploration
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• v.13 no.1
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• pp.96-101
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• 2010

A pulse radar system has been developed recently to detect dormant underground tunnels that are deeply located at depths of hundreds of metres. To check the ability of the radar system to detect an obliquely oriented tunnel, five different borehole pairs in the tunnel test site were chosen so that the horizontal lines-of-sight cut the tunnel axis obliquely, in $15^{\circ}$ steps. The pulse radar signatures were measured over a depth range of 20 m around the centre of the air-filled tunnel. Three canonical parameters, consisting of the arrival time, attenuation, and dispersion time were extracted from the first and second peaks of the measured radar signatures. Using those parameters, the radar system can detect obliquely oriented tunnels at various angles up to 45 from the transmitter-receiver line of sight.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.60.2-60.2
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• 2015

Since its detection in 1980, the $8-{\mu}m$ north-polar brightening of $CH_4$ on Juptier has not moved from $180^{\circ}$ (SysIII) longitude. The $8-{\mu}m$ $CH_4$ brightening is mostly thermal and very similar to that of $13-{\mu}m$ $C_2H_2$ emissions, but the morphology of these hydrocarbon north-polar brightenings are very different from that of the $3-{\mu}m$ $H_3{^+}$ auroral oval suggesting a significantly different excitation process yet unknown heating mechanism. Recently, Kim et al. (submitted to Icarus, 2015) found that that the center of the $3-{\mu}m$ $CH_4$ northern bright spot is located at ${\sim}200^{\circ}$ (SysIII) longitude, which is ${\sim}20^{\circ}$ west from the center of the $8-{\mu}m$ north-polar bright spot, and it does not coincide with the $3-{\mu}m$ $H_3{^+}$ bright spot. They found significantly high temperatures (500 ~ 850K) from $CH_4$ rotational lines on the $3-{\mu}m$ bright spot above the $1-{\mu}bar$ pressure level, while we find cooler temperatures (<350K) over the the $8-{\mu}m$ spot. They also found that the upper states of the $3-{\mu}m$ $CH_4$ bands are mostly populated by non-thermal excitations, such as auroral particle precipitations and/or Joule heatings in contrast to the $8-{\mu}m$ thermal emission. This finding indicates that the $10-{\mu}m$ hydrocarbon brightening is confined to low altitudes below the $1-{\mu}bar$ level eliminating the long-suggested possibility of direct auroral bombardments while opening a new possibility of dynamical origin for the $10-{\mu}m$ brightening.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.6
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• pp.479-487
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• 2020

A new double-pulse laser system that combines Raman and laser induced plasma spectroscopy (LIPS) in a single unit is proposed. The study attempts to enhance the laser induced plasma signals while simultaneously extracting the desired molecular signals from Raman spectroscopy. In low pressure conditions such as the lunar atmosphere, the measuring of plasma emission is hard because of the low electron density and short persistence time causing a rapid plasma expansion. Furthermore, in the integration of the detecting system aimed at space exploration, the minimization of laser system is important in terms of the payload mass. Simultaneous molecular and atomic detection that gave highly resolved spectral data at pressure below 0.07 torr is demonstrated amongst eight rock samples test. The plasma stacking produced from the double-pulse laser enhanced the signal intensity of calcium and oxygen lines in calcite matrix by twofold, compared to a conventional LIPS.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3429-3436
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• 2013

Cervical cancer is a major health problem worldwide and is the most frequent cause of cancer in women in India. Early detection and affordable drugs with clinical efficacy have to go hand-in-hand in order to comprehensibly address this serious health challenge. Plant-based drugs with potent anticancer effects should add to the efforts to find a cheap drug with limited clinical side effects. Keeping this very purpose in mind, an attempt has been made in this review to explore the potential of plant extracts or constituents known to exhibit antitumorigenic activity or exert cytotoxic effect in human cervical carcinoma cells. Alkaloids such as those isolated from C. vincetoxicum and T. Tanakae, naucleaorals A and B, isolated from the roots of N. orientalis, (6aR)-normecambroline, isolated from the bark of N. dealbata appear promising in different human cervical carcinoma cells with the $IC_{50}$ of 4.0-8 ${\mu}g/mL$. However, other compounds such as rhinacanthone and neolignans isolated from different plants are not far behind and kill cervical cancer cells at a very low concentrations. Among plant extracts or its constituents that enhance the effect of known anticancer drugs, noni, derived from the plant M. citrifolia perhaps is the best candidate. The cytotoxic potency and apoptotic index of cisplatin was found to significantly enhanced in combination with noni in different human cervical carcinoma cells and it therefore holds significance as promising herbal-based anticancer agent. However, efficacy needs to be further investigated in various cervical cell lines and more importantly, in in vivo cervical cancer models for possible use as an alternative and safe anticancer drug.

• Journal of Cadastre & Land InformatiX
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• v.45 no.2
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• pp.117-130
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• 2015

A least squares method for adjusting the horizontal network satisfies the conditions which is minimizing the sum of the squares of errors based on probability theory. This research compared accuracy of 3rd cadastral control points adjusted by traditional and least square method with respect to the result of Network-RTK. Test results showed the least square method more evenly distribute closure error than traditional method. Mean errors of least square and traditional adjusting method are 2.7cm, 2.2cm respectively. In addition, blunder in angle observations can be detected by comparing position errors which calculated by forward and backward initial coordinates. However, distance blunder cannot offer specific observation line occurred mistake because distance error propagates several observation lines which have similar directions.

• Journal of The Korean Astronomical Society
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• v.37 no.5
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• pp.387-392
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• 2004

X-ray observations of galaxy clusters have played an important role in cosmology, especially in determining the cosmological density parameter and the fluctuation amplitude. While they represent the bright side of the universe together with the other probes including the cosmic microwave background and the Type Ia supernovae, the resulting information clearly indicates that the universe is dominated by dark components. Even most of cosmic baryons turns out to be dark. In order to elucidate the nature of dark baryons, we propose a dedicated soft-X-ray mission, DIOS (Diffuse Intergalactic Oxygen Surveyor). Recent numerical simulations suggest that approximately 30 to 50 percent of total baryons at z = 0 take the form of the warm-hot intergalactic medium (WHIM) with $10^5K < T < 10^7K $which has evaded the direct detection so far. The unprecedented energy resolution (${\~} 2eV$) of the XSA (X-ray Spectrometer Array) on-board DIGS enables us to identify WHIM with gas temperature $T = 10^6 {\~} 10^7K$ and overdensity $\delta$ = 10 ${\~}$ 100 located at z < 0.3 through emission lines of OVII and OVIII. In addition, WHIMs surrounding nearby clusters are detectable with a typical exposure time of a day, and thus constitute realistic and promising targets for DIOS.