• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.34.2-34.2
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• 2013

Star formation beyond the galaxy discs and the principles governing it have attracted a lot of recent attention and the advent of ultraviolet (UV) and mid-infrared (MIR) telescopes like the GALEX and Spitzer have enabled major advances in such studies. In order to study the HI gas properties such as the morphology, kinematics and column density distributions, and their correlation with the star forming zones, especially in the tidal bridges, tails and debris, we carried out an HI survey of a set of Spitzer-observed interacting systems using the Giant Metrewave Radio Telescope (GMRT). Here we present results from three of these systems, Arp86, Arp181 and Arp202. In Arp86, we detect excellent star-gas correlation in the star forming tidal bridges and tails. In Arp181, we find the two interacting galaxies to be highly gas depleted and the entire gas of the system is found in the form of a massive tidal debris about 70 kpc from the main galaxies. In all three cases, Arp86, Arp181 and Arp202, the tidal debris seem to host ongoing star formation. We also detect three new candidate tidal dwarf galaxies (TDG) in these systems with large quantities of gas associated with them.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.169-173
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• 2017

We provide a new physical insight on the hot molecular clouds near the nucleus of the obscured AGNs. We performed near-infrared spectroscopic observations of heavily obscured AGNs in order to reveal physical characteristics of molecular clouds, especially focused on the CO fundamental ro-vibrational absorption around $4.7{\mu}m$. We have made systematic moderate-resolution spectroscopic observations toward 30 representative (U)LIRGs using the AKARI/IRC, and some of the ULIRGs showed the strong CO absorption feature. For three bright (U)LIRGs that show a steep red continuum with the deep CO absorption feature, IRAS 08572+3915, UGC 05101, and IRAS 01250+2832, we have also made high-resolution spectroscopic observations using the Subaru/IRCS. We have successfully detected many absorption lines up to highly excited rotational levels, and these lines are very deep and extremely broad. The derived physical conditions of molecular clouds are extreme; the gas temperature is as high as several 100 to a 1000 K, the $H_2$ column density is larger than $10^{22}cm^{-2}$, and the gas density is greater than $10^7cm^{-3}$. Such hot and dense molecular clouds must exist around the central engine of the AGN.

• Journal of computational fluids engineering
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• v.19 no.4
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• pp.68-74
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• 2014

This computational study features the transient compressible and inviscid flow analysis on a metallic plasma discharge from the opposing composite electrodes which is subjected to pulsed electric power. The computations have been performed using the flux corrected transport algorithm on the axisymmetric two-dimensional domain of electrode gap and outer space along with the calculation of plasma compositions and thermophysical properties such as plasma electrical conductivity. The mass ablation from aluminum electrode surfaces are modeled with radiative flux from plasma column experiencing intense Joule heating. The computational results shows the highly ionized and highly under-expanded supersonic plasma discharge with strong shock structure of Mach disk and blast wave propagation, which is very similar to muzzle blast or axial plasma jet flows. Also, the geometrical effects of composite electrodes are investigated to compare the amount of mass ablation and penetration depth of plasma discharge.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.1
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• pp.121-130
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• 1996

Adsorption isotherms of three trihalomethanes(THMs: $CHCl_3$, $CHBrCl_2$ and $CHBr_2Cl$) and the other organics(p-chlorophenol and sucrose)on activated carbon fibers(ACFs) were measured. Adsorption capacities of the ACFs for these THMs were found to be comparable with or slightly larger than those of granular activated car bons(GACs) which have been widely used for trihalomethanes control in drinking water. Also, the breakthrough curve prediction was successfully carried out using a mathematical model on basis of the assumption that the adsorption equilibrium is instantaneously established when a THM solution contacts the ACF. In practice, THM removal from drinking water was investigated at water works using benchscale ACF adsorptJOn columns. The volume of water treated at a space velocity(SV) of about $100h^{-1}$ was approximately 40 l/g-ACF. The practical adsorption capacities of PCP and sucrose in column adsorption were in good agreement with those of theoretically calculated results using the batch adsorption measurments. And the saturation time model of these substrates in the columns was also agreed succesfully with practical measurments.

• Korean Institute of Interior Design Journal
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• v.25 no.6
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• pp.32-39
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• 2016

The purpose of this study is create a comparative analysis of the characteristics of various materials which were used on the outer wall of F.L.Wright's works. The research results will be summarized as follows: 1) Wright thought that the outer wall was not just a physical object which divides the space of a house but it includes the image of the total exterior form, as well as, the economical factors of the age. 2) He tried to sublimate architectural image of his own style with the change of time because he recognized difficulties and limitations of traditional materials and economic feasibility. 3) He used nature-friendly material like wood and brick which were used in various methods of his natural architectural concept. 4) Some of Wright's early works were acculturated by classical architectural components such as the column to emphasize verticality of architectural form. The columns play a division role in the face of the outer wall creating a dynamic image and this also controls the amount of light that enters inside the house.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.4
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• pp.135-142
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• 2012

This study is aimed to investigate the dimension feature of the plane about the economic type farming village Korean-style house progressed in the Chonnam province and Longitudinal feature and tries to reveal this feature through the comparing analysis with the traditional house positioned in the Chonnam province. This result is as follows. First, the main feature in plane is the setting up the column interval in front when comparing the house of Happy Village and traditional house. In case house of the Happy Village, after firstly fixed the limited scales, sizes are determined, this is due to control the set up in the post interval in this in range. Second, in the case of the traditional houses, 0.68 ratio of the building height about the side length and 0.19 ratio of the eaves extrusion about the side length are consistent ratio about dimensions. However, there is no consistent ratio or fixed law, the various dimensions show up in case of the house of Happy Village. It will be inevitable that space of the post increases for the convenience of life of the modern people. However, it has to sublate and to disregard as the identity of the morphological shown up in the Korean-style house the more various construction standards will need to be presented.

• Advances in Computational Design
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• v.3 no.4
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• pp.385-404
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• 2018

The study investigated an area of sustainable structural design that is often overlooked in practical engineering applications. Specifically, a novel method to simultaneously optimise the cost and embodied carbon performance of steel building structures was explored in this paper. To achieve this, a parametric design model was developed to analyse code compliant structural configurations based on project specific constraints and rigorous testing of various steel beam sections, floor construction typologies (precast or composite) and column layouts that could not be performed manually by engineering practitioners. Detailed objective functions were embedded in the model to compute the cost and life cycle carbon emissions of the different material types used in the structure. Results from a comparative numerical analysis of a real case study illustrated that the proposed optimisation approach could guide structural engineers towards areas of the solution space with realistic design configurations, enabling them to effectively evaluate trade-offs between cost and carbon performance. This significant contribution implied that the optimisation model could reduce the time required for the design and analysis of multiple structural configurations especially during the early stages of a project. Overall, the paper suggested that the deployment of automated design procedures can enhance the quality as well as the efficiency of the optimisation analysis.

• Journal of Korean Neurosurgical Society
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• v.57 no.1
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• pp.61-64
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• 2015

A number of dynamic stabilization systems have been used to overcome the problems associated with spinal fusion with rigid fixation recently and the demand for an ideal dynamic stabilization system is greater for younger patients with multisegment disc degeneration. Nitinol, a shape memory alloy of nickel and titanium, is flexible at low temperatures and regains its original shape when heated, and the Nitinol shape memory loop (SML) implant has been used as a posterior tension band mostly in decompressive laminectomy cases because the Nitinol implant has various characteristics such as high elasticity and a tensile force, flexibility, and biological compatibility. The reported short-term outcomes of the application of SMLs as posterior column supporters in cervical and lumbar decompressive laminectomies seem to be positive, and complications are minimal except for the rare occurrence of pullout and fracture of the SML. However, there was no report of neurological complications related to neural compression in spite of the use of the loop of SML in the epidural space. The authors report a case of delayed development of radiating pain caused by subsidence of the SML resulting epidural compression.

• Journal of Multimedia Information System
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• v.2 no.2
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• pp.193-206
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• 2015

In this paper a new approach for image encryption based on quadruple encryption with dual chaotic maps is proposed. The encryption process is performed with quadruple encryption by invoking the encrypt and decrypt routines with different keys in the sequence EDEE. The decryption process is performed in the reverse direction DDED. The key generation for the quadruple encryption is achieved with a 1D Circle map. The chaotic values for the encrypt and decrypt routines are generated by using a 2D Henon map. The Encrypt routine E is composed of three stages i.e. permutation, pixel value rotation and diffusion. The permutation is achieved by: row and column scrambling with chaotic values, exchanging the lower and the upper principal and secondary diagonal elements based on the chaotic values. The second stage circularly rotates all the pixel values based on the chaotic values. The last stage performs the diffusion in two directions (forward and backward) with two previously diffused pixels and two chaotic values. The security and performance of the proposed scheme are assessed thoroughly by using the key space, statistical, differential, entropy and performance analysis. The proposed scheme is computationally fast with security intact.

• Publications of The Korean Astronomical Society
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• v.16 no.1
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• pp.15-20
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• 2001

We observed the thermal transitions of SiO (J=I-0, 2-1) and $^{29}SiO$ (J=l-O) toward the Sgr A molecular clouds. The distribution and the velocity structure of SiO are very similar to previous results for 'quiet' interstellar molecules. We think· that the SiO has been well mixed with other molecules such as $H_2$ which may indicate that the formation of Sgr A molecular clouds was affected by the activities, such as shock waves or energetic photons, from the Galactic center in large scales. The total column density of SiO is about $4.1\times10^{14} cm^{-2}$ and the fractional abundance $SiO/H_2$ appears to be about 10 times larger than those of other clouds in the central region of our galaxy. The derived values are thought to be lower limits since the optical depths of the observed SiO lines are not very thin. The formation of SiO has been known to be critically related to shocks, and our results provide informative data on the environment of our Galactic center.