• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.504-505
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• 2008

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.2
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• pp.183-190
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• 2009

The aim of this study is to find the condition of forming the favorable nanotubes by anodizing with NaF and $H_3PO_4$. Machined Ti discs were used for anode, and Platinum net was used for cathode. For electrolyte, $H_3PO_4$ and NaF solution were mixed. We controlled voltage, electrolyte concentration, anodizing time and formed nanotubes on Ti discs. After that, these were washed with distilled water for 24 hours and dried in the $40^{\circ}C$ oven for 24 hours. The surface structure of specimens were analyzed. The results were as follows : At 0.5 wt % NaF, according as increasing voltage and anodizing time, early state of nucleating pores were generated. At 1.0 wt % NaF, 20 V, 20 & 25 min, well-formed nanotubes were observed. At 1.0 wt % NaF, 30 V, structure of nanotube became bigger and interconnected. At 2.0 wt % NaF, no nanotubes were formed and it was unrelated with voltage and time. At 1.0 wt % NaF, 20 V, 20 - 25 min, well-ordered nanotubes were generated on Ti discs. For the formation of favorable nanotubes, it is considered that proper parameters such as electrolyte concentration, voltage, anodizing time are necessary according to the kind of electrolytes.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.5
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• pp.555-560
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• 2014

In order to improve spectrum sensitivity of photodiode for detection of the laser wavelength at 850 nm ~ 1000 nm of near-infrared band, this study has produced silicon-based photodiode whose area is $5000{\mu}m{\times}2000{\mu}m$, and the thickness is $280{\mu}m$. It was packed by the TO-5 type. The electrical properties of the dark currents have valued of approximately 0.1 nA for 5 V reverse bias, while the capacitance showed 32.5 pF at frequency range of 1 kHz and about 32.4 pF at the range of 200 kHz for 0 V. In addition, the rising time of output signal was as fast response as 20.92 ns for 10V. For the optical properties, the best spectrum sensitivity was 0.57 A/W for 890 nm, while it was relatively excellent value of 0.37 A/W for 1,000 nm. Over all, there were good spectrum sensitivity for this diode over the range of 870 ~ 920 nm.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.569-572
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• 2014

This paper presents a CMOS switched-capacitor interface circuit for MEMS capacitive sensors. It consist of a capacitance to voltage converter(CVC), a second-order ${\Sigma}{\Delta}$ modulator, and a comparator. A bias circuit is also designed to supply constant bias voltages and currents. This circuit employes the correlated-double-sampling(CDS) and chopper-stabilization(CHS) techniques to reduce low-frequency noise and offset. The designed CVC has a sensitivity of 20.53mV/fF and linearity errors less than 0.036%. The duty cycle of the designed ${\Sigma}{\Delta}$ modulator output increases about 5% as the input voltage amplitude increases by 100mV. The designed interface circuit shows linearity errors less than 0.13%, and the current consumption is 0.73mA. The proposed circuit is designed in a 0.35um CMOS process with a supply voltage of 3.3V. The size of the designed chip including PADs is $1117um{\times}983um$.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.179-181
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• 2003

$F(ab`)_2$-ELISA and direct antigen coating-ELISA (DAC-ELISA) were evaluated in the detection of purified Bombyx mori nuclear polyhedrosis virus (BmNPV) and nuclear polyhedrosis virus infection in silkworm larvae inoculated with BmNPV polyhedra. Although nanogram levels of BmNPV was detected in both DAC- and $F(ab`)_2$-ELISA, similar concentrations of antigen was detected in case of F(ab’)$_2$-ELISA even at higher dilution of antibody (up to 1 : 20 K). One hundred percent nuclear polyhedrosis infection was detected 6 hrs after inoculation in BmNPV infected silkworm larvae by $F(ab`)_2$-ELISA. On the other hand, detection of 100% infection was observed only three days after inoculation in DAC-ELISA. In this study, it was observed $F(ab`)_2$-ELISA was more sensitive than DAC-ELISA in the detection of purified BmNPV as well as nuclear polyhedrosis infection in silkworm larvae.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.204-210
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• 2012

Nickel oxide thin films with 2.3 ${\mu}m$ thickness were prepared in order to overcome limitations of thickness with nm dimension by anodizing. For the electrolyte, ethylene glycol was used as solvent, and $NH_4F$ was added for source of $F^-$ ions. The anodizing experiments were carried out on various voltages such as 40, 60 V and 80 V for 12 hours. The thickness of NiO was changed according to the anodizing time and the voltage. However, destruction of Ni caused by rapid oxidation reaction occurred at 80 V. XRD results show that NiO was successfully created by anodizing.

• Kyungpook Mathematical Journal
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• v.59 no.3
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• pp.515-523
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• 2019

Consider a graph G of order n and maximum degree ${\Delta}$. Let $f:V(G){\rightarrow}\{0,1,{\cdots},{\lceil}{\frac{{\Delta}}{2}}{\rceil}+1\}$ be a function that labels the vertices of G. Let $B_0=\{v{\in}V(G):f(v)=0\}$. The function f is a strong Roman dominating function for G if every $v{\in}B_0$ has a neighbor w such that $f(w){\geq}1+{\lceil}{\frac{1}{2}}{\mid}N(w){\cap}B_0{\mid}{\rceil}$. In this paper, we study the bounds on strong Roman domination numbers of the Cartesian product $P_m{\square}P_k$ of paths $P_m$ and paths $P_k$. We compute the exact values for the strong Roman domination number of the Cartesian product $P_2{\square}P_k$ and $P_3{\square}P_k$. We also show that the strong Roman domination number of the Cartesian product $P_4{\square}P_k$ is between ${\lceil}{\frac{1}{3}}(8k-{\lfloor}{\frac{k}{8}}{\rfloor}+1){\rceil}$ and ${\lceil}{\frac{8k}{3}}{\rceil}$ for $k{\geq}8$, and that both bounds are sharp bounds.

• Journal of the Korean Mathematical Society
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• v.48 no.3
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• pp.551-563
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• 2011

Let ${\kappa}$ be a positive integer and let G be a simple graph with vertex set V(G). A function f : V (G) ${\rightarrow}$ {-1, 1} is called a signed total ${\kappa}$-dominating function if ${\sum}_{u{\in}N({\upsilon})}f(u){\geq}{\kappa}$ for each vertex ${\upsilon}{\in}V(G)$. A set ${f_1,f_2,{\ldots},f_d}$ of signed total ${\kappa}$-dominating functions of G with the property that ${\sum}^d_{i=1}f_i({\upsilon}){\leq}1$ for each ${\upsilon}{\in}V(G)$, is called a signed total ${\kappa}$-dominating family (of functions) of G. The maximum number of functions in a signed total ${\kappa}$-dominating family of G is the signed total k-domatic number of G, denoted by $d^t_{kS}$(G). In this note we initiate the study of the signed total k-domatic numbers of graphs and present some sharp upper bounds for this parameter. We also determine the signed total signed total ${\kappa}$-domatic numbers of complete graphs and complete bipartite graphs.

• Communications of the Korean Mathematical Society
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• v.21 no.2
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• pp.261-272
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• 2006

In this paper, we define the sequence spaces: $[V,{\lambda},f,p]_0({\Delta}^r,E,u),\;[V,{\lambda},f,p]_1({\Delta}^r,E,u),\;[V,{\lambda},f,p]_{\infty}({\Delta}^r,E,u),\;S_{\lambda}({\Delta}^r,E,u),\;and\;S_{{\lambda}0}({\Delta}^r,E,u)$, where E is any Banach space, and u = ($u_k$) be any sequence such that $u_k\;{\neq}\;0$ for any k , examine them and give various properties and inclusion relations on these spaces. We also show that the space $S_{\lambda}({\Delta}^r, E, u)$ may be represented as a $[V,{\lambda}, f, p]_1({\Delta}^r, E, u)$ space. These are generalizations of those defined and studied by M. Et., Y. Altin and H. Altinok [7].

• Nuclear Engineering and Technology
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• v.5 no.1
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• pp.38-43
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• 1973

The spin-rotation constants of the proton and tile fluorine nucleus in C $H_4$, Si $H_4$, Ge $H_4$, C $F_4$, Si $F_4$ and Ge $F_4$ were determined experimentally by the molecular beam magnetic resonance method. From the Hamiltonian and the high field approximation, the quantized energy level is given by the following equation. W $m_{I}$ $m_{J}$=- $g_{I}$ $m_{I}$H- $g_{J}$ $m_{J}$H- $C_{av}$ $m_{I}$ $m_{J}$, where $c_{av}$ is one third of the trace of the C tensor. In the nuclear resonance experiment, the proton and the fluorine nuclear resonance curves consist of many unresolved lines given by v=- $g_{J}$H- $C_{av}$ $m_{I}$, and a Gaussian approximation is made to correlate $c_{av}$ to the experimentally obtained half-width of the resonance curve. In the rotational resonance experiment, the five resonance peaks as predicted by v=- $g_{I}$H- $c_{av}$ $m_{I}$, $m_{I}$=0, $\pm$1 and $\pm$2, were all observed. The magnitude of car was determined by measuring the frequency distance between two adjacent peaks. The sign of $c_{av}$ was determined by the side peak suppression technique. The technique is described, and the sign and magnitude of the spin-rotation constant cav are summarized as following: for C $H_4$ -10.3$\pm$0.4tHz(from the rotational resonance), for SiH +3.71$\pm$0.08kHz(from the nuclear resonance), for Ge $H_4$+3.79$\pm$0.13kHz(from the nuclear resonance), for C $F_4$, -6.81$\pm$0.08kHz(from the rotational resonance), for Si $F_4$, -2.46$\pm$0.06kHz(from the rotational resonance), and finally for Ge $F_4$-1.84$\pm$0.04kHz(from the rotational resonance).onal resonance).esonance).