• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.905-911
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• 2011

The possible minimum structures of $C_{60}(CH_2)_nOH$ (n=0~2) and $C_{60}(OH)_2$have been optimized using density functional theory (DFT) with the 6-311G (d,f) basis set. The harmonic vibrational frequencies and IR intensities are also determined to confirm that all the optimized geometries are true minima. Also zero-point vibrational energies (ZPVE) have been considered to predict the binding energies. The predicted binding energy of $C_{60}CH_2OH$ is about 10 kcal/mol more stable than the binding energy of $C_{60}OH$.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.2
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• pp.101-107
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• 2012

This study describes a proposed method of converting an input sound signal into a color image by emulating human synesthetic skills which make it possible to associate an sound source with a specific color image. As a first step of sound-to-image conversion, features such as fundamental frequency(F0) and energy are extracted from an input sound source. Then, a musical scale and an octave can be calculated from F0 signals, so that scale, energy and octave can be converted into three elements of HSI model such hue, saturation and intensity, respectively. Finally, a color image with the BMP file format is created as an output of the process of the HSI-to-RGB conversion. We built a basic system on the basis of the proposed method using a standard C-programming. The simulation results revealed that output color images with the BMP file format created from input sound sources have diverse hues corresponding to the change of the F0 signals, where the hue elements have different intensities depending on octaves with the minimum frequency of 20Hz. Furthermore, output images also have various levels of chroma(or saturation) which is directly converted from the energy.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.4
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• pp.293-298
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• 1976

1) The decrease in strength of netting twines at the twisted joint is regarded to be due mainly to tile frictional force between plied yarns, but tile rate of decresae is within $5\%$ in filament twines and 5 to $10\%$ in spun twines. 2) The variation of the twisted joint strength with the angle between the two adjacent bars draws a parabola flaying the minimum value at tile angle of $90^{\circ}$. The minimum value was revealed as about $90\%$ of the strength at the angle of $0^{\circ}$ in wet spun twiness, but regarded to hi negligibly small filament twines. 3) The knot strength is about $30{\pm}5\%$of the twisted joint strength.

• Bulletin of the Korean Mathematical Society
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• v.56 no.1
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• pp.1-12
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• 2019

For a finite poset $P=(X,{\preceq})$ the fractional weak discrepancy of P, denoted $wd_F(P)$, is the minimum value t for which there is a function $f:X{\rightarrow}{\mathbb{R}}$ satisfying (1) $f(x)+1{\leq}f(y)$ whenever $x{\prec}y$ and (2) ${\mid}f(x)-f(y){\mid}{\leq}t$ whenever $x{\parallel}y$. In this paper, we determine the range of the fractional weak discrepancy of (M, 2)-free posets for $M{\geq}5$, which is a problem asked in [9]. More precisely, we showed that (1) the range of the fractional weak discrepancy of (M, 2)-free interval orders is $W=\{{\frac{r}{r+1}}:r{\in}{\mathbb{N}}{\cup}\{0\}\}{\cup}\{t{\in}{\mathbb{Q}}:1{\leq}t<M-3\}$ and (2) the range of the fractional weak discrepancy of (M, 2)-free non-interval orders is $\{t{\in}{\mathbb{Q}}:1{\leq}t<M-3\}$. The result is a generalization of a well-known result for semiorders and the main result for split semiorders of [9] since the family of semiorders is the family of (4, 2)-free posets.

• Speech Sciences
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• v.7 no.1
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• pp.217-232
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• 2000

In this study, I investigate the role of post-consonantal fundamental frequency (F0) as a cue for automatic distinction of types of Korean stops and affricates. Rather than examining data obtained by restricting contexts to a minimum to prevent the interference of irrelevant factors, a relatively natural speaker independent speech corpus is analysed. Automatic and statistical approaches are adopted to annotate data, to minimise speaker variability, and to evaluate the results. In spite of possible loss of information during those automatic analyses, statistics obtained suggest that vowel F0 is a useful cue for distinguishing manners of articulation of Korean non-continuant obstruents having the same place of articulation, especially of lax and aspirated stops and affricates. On the basis of the statistics, automatic classification is attempted over the relevant consonants in a specific context where the micro-prosodic effects appear to be maximised. The results confirm the usefulness of this effect in application for Korean phone recognition.

• Communications of the Korean Mathematical Society
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• v.29 no.2
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• pp.359-366
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• 2014

A three-valued function f defined on the vertices of a digraph D = (V, A), $f:V{\rightarrow}\{-1,0,+1\}$ is a minus total dominating function(MTDF) if $f(N^-(v)){\geq}1$ for each vertex $v{\in}V$. The minus total domination number of a digraph D equals the minimum weight of an MTDF of D. In this paper, we discuss some properties of the minus total domination number and obtain a few lower bounds of the minus total domination number on a digraph D.

• Korean Journal of Ichthyology
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• v.23 no.2
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• pp.111-118
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• 2011

The maturation and spawning of filefish, Stephanolepis cirrhifer were investigated using samples randomly collected in the East Sea of Korea from August 2009 to July 2010. The total length at 50% group maturity of filefish was estimated to be 11.7 cm. Based on monthly changes in maturity stages and gonadosomatic index (GSI), the spawning period was estimated to be from June to September, and the peak spawning from August to September. The fecundity (F) ranged from 693,981 eggs to 7,383,429 eggs at 23.6 cm between minimum and maximum total length (TL) 13.3 cm and 23.6 cm respectively. The relationship between TL and F was expressed as F=$12.19TL^{4.208}$ ($R^2$=0.727). The sex ratio of male to female was 1 to 0.9.

• Journal of Korea Water Resources Association
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• v.53 no.8
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• pp.617-626
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• 2020

This study investigates changes of bifurcation discharge ratio, flow velocity distributions and characteristics of separation zone due to variation of bifurcation angle by using TELEMAC-2D model. When the bifurcation angle is reduced from 90° to 45° without changing the boundary conditions, the bifurcation discharge ratio increased by 1.5 times from 0.523 to 0.785 because of increasing the radius of curvatures, the inertia force of the downstream flow, and the pressure gradient by the downstream boundary conditions. The bifurcation discharge ratio increases non-linearly whenever the bifurcation angle decreases by 15° intervals from 90° to 45° in flow with the upstream Froude number of 0.45 to 0.74. In flow with a maximum Froude number of 0.74, the rate of increase for bifurcation discharge ratio is 31.1% and the minimum value. When the Froude number is 0.58, the bifurcation discharge ratio is 0.7 or less, and the maximum rate of increase for that ratio is 53.5%. As the upstream Froude number decreases less than 0.58, the bifurcation discharge ratio exceeds 0.7, and the rate of increase decreases. When the upstream Froude number is 0.4 higher, the dimensionless width and length changing ratio of the separation zone are about 2.56 and 5.5 times higher than in 0.4 or less.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.4
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• pp.26-33
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• 2010

This paper presents a multi-channel capacitive touch sensing unit for SoC applications. This unit includes a simple common processing unit and switch array to detect the touch sensing input by capacitive-time(C-T) conversion method. This touch sensor ASIC is designed based on the Capacitive-Time(C-T) conversion method to have advantages of small current and chip area, and the minimum resolution of the unit is 41 fF per count with the built-in sensing oscillator, LDO regulator and $I^2C$ for no additional external components. This unit is implemented in 0.18 um CMOS process with dual supply voltage of 1.8 V and 3.3 V. The total power consumption of the unit is 60 uA and the area is 0.26 $mm^2$.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.3
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• pp.423-431
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• 2002

An experimental study is conducted to investigate the effect of two-frequency forcing on turbulent flow behind a backward-facing step at the Reynolds number of 27000 based on the step height. The forcing is provided from a thin slit located at the edge of the backward-facing step to increase mixing behind the backward-facing step and consequently to reduce the reattachment length. With single frequency forcing, the minimum reattachment length is obtained at the non-dimensional forcing frequency (F) of St$\_$h/ = 0.29. With two-frequency forcing, a subharmonic frequency (F/2) or biharmonic frequency (2F) is combined with the fundamental frequency (F), i.e. (F, F/2) or (F, 2F) forcing is applied. In the case of (F, F/2) forcing, the reattachment length is not much sensitive to the phase difference between F and F/2. However, the reattachment length significantly depends on the phase difference between F and 2F in the case of (F, 2F) forcing. At a certain range of the phase difference, the reattachment length becomes smaller than that of the single frequency forcing.