• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.7
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• pp.634-640
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• 2003

This paper is to be researched into ozone generation character of Bi-Ti-Si type high dielectric yield ceramic catalyst discharge tube. And conditions of basic experiment are the outside diameter of discharge tube : 52 mm, the length of discharge tube : 350 mm, the frequence : 900 Hz, the temperature of cooling water : 25 $^{\circ}C$, quantity of flow : 5, 10, 20 l/min, pressure : 1.2, 1.4, 1.6 atm, and distance of discharge gap : 0.4, 0.6, 0.8 mm. Ozone generation characteristics were measured to consumption power. At quantity of flow : 20 l/min, discharge gap : 0.6 mm, pressure : 1.6, and consumption power : 150 W, Maximum ozone generation efficiency of 175 g/kWh was obtained. Maximum ozone generation efficiency was measured below the flow quantity of 20 l/min at below pressure of 1.6 atm. However, Maximum ozone generation efficiency was measured over the flow quantity of 20 l/min at over pressure of 1.6 atm.

• Korean Journal of Crystallography
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• v.11 no.1
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.67.4-68
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• 2015

We present a multi-wavelength observational study of a low-mass star-forming region, L1251-C, with observational results at wavelengths from the near-infrared to the millimeter. Spitzer Space Telescope observations confirmed that IRAS 22343+7501 is a small group of protostellar objects. The extended emission to east-west direction with its intensity peak at the center of L1251A has been detected at 350 and 850 mm with the CSO and JCMT telescopes, tracing dense envelope materials around L1251A. The single-dish data from the KVN and TRAO telescopes show inconsistencies between the intensity peaks of several molecular line emission and that of the continuum emission, suggesting complex distributions of molecular abundances around L1251A. The SMA interferometer data, however, show intensity peaks of CO 2-1 and $^{13}CO$ 2-1 located at the position of IRS 1, which is both the brightest source in IRAC image and the weakest source in the 1.3 mm dust continuum map. IRS 1 is the strongest candidate for being the driving source of a newly detected the compact CO 2-1 outflow. Over the whole region ($14^{\prime}{\times}14^{\prime}$) of L125l-C, 3 Class I and 16 Class II sources have been detected, including three YSOs in L1251A. A comparison with the average projected distance among 19 YSOs in L1251-C and that among 3 YSOs in L1251A suggests L1251-C is an example of low-mass cluster formation, where protostellar objects are forming in a small group.

• Korean Journal of Crystallography
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• v.11 no.3
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• pp.133-136
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• 2000

The molecular structure of [Cd(L)Cl]Cl·2H₂O(1)(L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,0/sup 1.18/,0/sup 7.12/]docosane) has been determined by X-ray diffraction. Crystallographic dta for 1: triclinic space group P1, a=9.671(1), b=10.784(1), c=12.679(2)Å, α=112.31(1), β=99.49(1), γ=93.95(1)°, V=1230.6(3)ų, Z=2, R=0.0779. The coordination of the cadmium atom is a distorted square-pyramid with four secondary amines of the macrocycle occupying the basal sites (Cd-N/sub av/=2.300(3)Å) and a terminal chlorine atom at the axial position with a Cd-Cl(1) distance of 2.463(2)Å.

• Korean Journal of Ecology and Environment
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• v.48 no.2
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• pp.139-145
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• 2015

To investigate seasonal (summer and fall) daily movement of Brachymystax lenok tsinlingensis that inhabit in upper part of the Nakdong River, we attached radio tags to seven individuals (summer: BL1-2; fall: BL3-7) and monitored them at an interval of 2 h. The survey results revealed that the average movement distance per day (m) (${\pm}SD$) of B. l. tsinlingensis was $182.4{\pm}79.2m$, and most of the individuals migrated within 1 km as their habitat boundary. The maximum movement distance per day (m) and the home range (m) during summer season were $550.5{\pm}75.5m$ and $649{\pm}53m$, respectively, compared to $283.8{\pm}55.1m$ and $186{\pm}32m$ during fall season. From these findings, it can be inferred that B. l. tsinlingensis exhibits seasonal changes in the distance of daily movement; however, it generally covers short distances without leaving the habitat boundaries during both seasons. The seasonal daily movement of B. l. tsinlingensis established in this study is expected to be useful in preserving their population.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.2C
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• pp.210-218
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• 2010

In order to improve the efficiency of frequency bandwidth, various modulation methods such as QAM and PSK have been widely used, and their variation APSK(Amplitude Phase Shift Keying) type modulation methods were proposed and are being used in some satellite communication systems. In this paper, a new constellation method named as $4L^2$-APSK is proposed, which places symbol points circularly as the existing APSK constellations do, but has different number of points and different distance between adjacent points on each layer. An equation for error probability in AWGN channel is also induced for $4L^2$-APSK. In addition, a new Gaussian noise channel is proposed in which noise variances are in the amplitude and in the phase and the two are not equal, and a method of obtaining error probabilities in this channel is also suggested. The equations for error probabilities are verified by computer simulations, and error probabilities of $4L^2$-APSK and QAM are analyzed and compared in the AWGN channel and the proposed noise channel, respectively.

• Journal of the Korean Society for Nondestructive Testing
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• v.11 no.1
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• pp.13-22
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• 1991

In this paper, 3-dimensional fracture phenomena in the local area near a through notch tip located between the surface and the canter were investigated by using embedded dyeing grids with the pitch of $50.8{\mu}$. It was confirmed that displacement V and square root of distance from notch tip $y^{1/2}$ are not proportional in the local area of $\sqrt{{\mid}y{\mid}}\;<\;0.3mm^{1/2}$ and the maximum shea strain ${\varepsilon}_{xymax}$ near a notch tip occurred at the curvature beginning point of the notch curve. It was also noted that the maximum strain ${\varepsilon}_{xymax}$ in the thickness direction occurred at the interior, where the ratio of the distance measured from surface to the half of thickness of specimen is 0.3.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1011-1014
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• 1999

Blood protein polymorphism of fowls in Laos was analyzed by electrophoresis. Blood samples were collected in the area of Viangchan, Louangphrabang and Pakxe. Out of 17 loci, polymorphism was detected at the following seven loci; ES-1, Amy-1, Akp-akp, Akp-2, Alb, Tf and Pas. The other ten loci; Amy-3, LDH, 6-PGD, PGM, PHI, To, MDH, Es-D, Hb-l, Hb-2 were noted to be monomorphic. The proportion of polymorphic loci $(P_{poly})$, the expected average heterozygosity per individual ($\bar{H}$), and the subdivision index $(G_{ST})$ of the native fowl in Laos was $0.412{\pm}0.123$, 0.106 and 0.026, respectively. Genetic distance between native fowls in Laos, Bangladesh, and Nepal was clustered in one group.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.264-270
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• 2006

In this research, volume reduction of activated sludge using electrolysis was studied to find an optimum condition using lab scale experiments. Wasted sludge was treated by electrolysis with controlling current density, chloride concentration, electrode distance, and reaction time. Volume of return sludge was reduced by 9.79% in average while maximum was 16.7%. Sludge volume reduction efficiency was affected by current density and reaction time. It was reversely proportional to the electrode distance. Especially current density was effective on the system performance significantly. Electric conductivity, salinity and COD were increased by electrolysis implying sludge disintegrated and converted to COD in part. An empirical equation for total solid removal efficiency by electrolysis was proposed by multiple linear regression analysis as: $TS_{rem}$(%) = 5.534 ${\times}$ current density (A/l) + 0.178 ${\times}$ reaction time (m) + 2.758.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.6986-6992
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• 2014

The generalized Voronoi graph (GVG) is a topological map of a constrained environment. This is defined in terms of workspace distance measurements using only sensor-provided information, with a robot having a maximum distance from obstacles, and is the optimum for exploration and obstacle avoidance. This is the safest path for the robot, and is very significant when studying the GVG edges of highly articulated robots. In previous work, the point-GVG edge and Rod-GVG were built with point robot and rod robot using sensor-based control. An attempt was made to use a higher degree of freedom robot to build GVG edges. This paper presents GVG-based a new local roadmap for the two-link robot in the constrained two-dimensional environment. This new local roadmap is called the two-identical-link generalized Voronoi graph (L2-GVG). This is used to explore an unknown planar workspace and build a local roadmap in an unknown configuration space $R^2{\times}T^2$ for a planar two-identical-link robot. The two-identical-link GVG also can be constructed using only sensor-provided information. These results show the more complex properties of two-link-GVG, which are very different from point-GVG and rod-GVG. Furthermore, this approach draws on the experience of other highly articulated robots.