• Journal of the Chungcheong Mathematical Society
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• v.35 no.2
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• pp.125-136
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• 2022

The goal of this paper is to introduce the notion of generalized symmetric bi-f-derivations in lattices and to study some properties of generalized symmetric f-derivations of lattice. Moreover, we consider generalized isotone symmetric bi-f-derivations and fixed sets related to generalized symmetric bi-f-derivations.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.30B no.11
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• pp.1-10
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• 1993

This paper proposes a High Performance Full-Swing BiCMOS (HiF-BiCMOS) circuit which improves on the conventional BiCMOS circuit. The HiF-BiCMOS circuit has all the merits of the conventional BiCMOS circuit and can realize full-swing logic operation. Especially, the speed of full-swing logic operation is much faster than that of conventional full-swing BiCMOS circuit. And the number of transistors added in the HiF-BiCMOS for full-swing logic operation is constant regardless of the number of logic gate inputs. The HiF-BiCMOS circui has high stability to variation of environment factors such as temperature. Also, it has a preamorphized Si layer was changed into the perfect crystal Si after the RTA. Remarkable scalability for power supply voltage according to the development of VLSI technology. The power dissipation of HiF-BiCMOS is very small and hardly increases about a large fanout. Though the Spice simulation, the validity of the proposed circuit design is proved.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.1
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• pp.15-18
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• 2009

To enhance near UV-visible absorption region and to applied phosphor convert-white LEOs (PC-WLEDs), a red phosphor composed of ${Y_2}{SiO_5}:\;EU^{3+}$, $Bi^{3+}$ compounds was prepared by the conventional solid-state reaction. The photoluminescence (PL) shown that samples were excited by near UV light 395 nm for measurement of PL spectra. Emission spectra of samples have shown red emissions at 612 nm ($^5D_0{\to}^7F_2$). The enhanced near $UV{\sim}$ visible excitation spectrum with a broad band centered at 258 nm and 282 nm originated in the transitions toward the charge transfer state (CTS) due to the $Eu^{3+}-Bi^{3+}-O^{2-}$ interaction. The other excitation band at $350\;nm{\sim}480\;nm$, corresponding to the transitions $^7F_0{\to}^5L_9$ (364 nm), $^7F_0{\to}^5G_3$ (381 nm), $^7F_0{\to}^5L_6$ (395 nm), $^7F_0{\to}^5D_3$, (415 nm) and $^7F_0{\to}^5D_2$ (466 nm), occurred due to enhanced the f-f transition increasing $Bi^{3+}$ and $Eu^{3+}$ ions. The PL intensity increased with increased as concentration of $Bi^{3+}$ and the emission intensity becomes with a maximum at 0.125 mol.

• Bulletin of the Korean Mathematical Society
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• v.47 no.1
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• pp.195-209
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• 2010

In this paper, we prove the generalized Hyers-Ulam stability of bi-homomorphisms in $C^*$-ternary algebras and of bi-derivations on $C^*$-ternary algebras for the following bi-additive functional equation f(x + y, z - w) + f(x - y, z + w) = 2f(x, z) - 2f(y, w). This is applied to investigate bi-isomorphisms between $C^*$-ternary algebras.

• MALSORI
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• no.35_36
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• pp.131-143
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• 1998

This study describes an algorithm for the F0 contour generation system for Korean sentences and its evaluation results. 400 K-ToBI labeled utterances were used which were read by one male and one female announcers. F0 contour generation system uses two classification trees for prediction of K-ToBI labels for input text and 11 regression trees for prediction of F0 values for the labels. Evaluation results of the system showed 77.2% prediction accuracy for prediction of IP boundaries and 72.0％ prediction accuracy for AP boundaries. Information of voicing and duration of the segments was not changed for F0 contour generation and its evaluation. Evaluation results showed 23.5Hz RMS error and 0.55 correlation coefficient in F0 generation experiment using labelling information from the original speech data.

• Speech Sciences
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• v.9 no.1
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• pp.89-110
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• 2002

Intonation is very difficult to describe and it is furthermore difficult to compare intonation between different languages because of their differences of intonation systems. This paper aims to compare some intonation phenomena between Korean, French and English. In this paper I will refer to ToBI (the Tone and Break Indices) which is a prosodic transcription model proposed originally by Pierrehumbert (1980) as a description tool. In the first part, I will summarize different ToBI systems, namely, K-ToBI (Korean ToBI), F-ToBI (French ToBI) and ToBI itself (English ToBI) in order to compare the differences of three languages within prosody. In the second part, I will analyze some tokens registered by Korean, French and American in different languages to show the difficulties of learning other languages and to find the prosodic cues to pronounce correctly other languages. The point of comparison in this study is the Accentual Phrase (AP) in Korean and in French and the intermediate phrase (ip) in English, which I will call ' subject phrase ' in this study for convenience.

• Journal of the Korean Ceramic Society
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• v.35 no.10
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• pp.1107-1112
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• 1998

We could obtan c-axis oriented $SrBi_2$$Ta_2$$O_9$ thin films on usual Pt(111)/Ti/$SiO_2$/Si(100) substrate using a r. f. magnetron sputtering technique. According to the increase of sputtering pressure from 250 to 300 mTorr the Bi content and degree of the c-a xis preferred orientation of $SrBi_2$$Ta_2$$O_9$ thin films were increased. By controlling Bi(or $Bi_2O_3$) loss from $SrBi_2$$Ta_2$$O_9$ thin films during post annealing and by inserting $Bi_2O_3$ layer in $SrBi_2$$Ta_2$$O_9$ thin films the effect of Bi content on the c-axis oriented growth of $SrBi_2$$Ta_2$$O_9$ thin films could be investigated without the effect of sputtering pressure. The degree of the c-axis preferred orientation of $SrBi_2$$Ta_2$$O_9$ thin films was increased with increasing with increasing Bi content by control of Bi(or $Bi_2O_3$) loss of $SrBi_2$$Ta_2$$O_9$ thin films. But the c-axis oriented growth of $SrBi_2$$Ta_2$$O_9$ thin films disappeared by the inserting of $Bi_2O_3$ lay-er in $SrBi_2$$Ta_2$$O_9$ thin films.

• Journal of IKEEE
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• v.3 no.2 s.5
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• pp.226-235
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• 1999

To investigate SPICE noise model and the behavior of its parameters, 1/f noise of NMOS devices fabricated by BiCMOS process is measured and compared to the various noise models and measured results. For the long channel devices, bias dependence of the drain current noise power spectral density $S_{Id}$ of NMOS is similar to the previous results. Equivalent gate noise power spectral density $S_{Vg}$ shows weak dependence on the gate and drain voltages in long channel NMOS as the previous results. However, it is shown that most of published noise models are difficult to apply to short channel devices. Therefore, in this study, with comparison of our experimental results, we have tried to find the model of 1/f noise, appropriate for our NMOS device fabricated by BiCMOS process.

• Korean Journal of Materials Research
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• v.8 no.7
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• pp.659-663
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• 1998

The effect of Bi-substitution in $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ ceramic was studied on the formation of crystal phases, microstructure, and microwave dielectric properties. $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$, solid solution (0$\leq$x$\leq$0.2) were formed by Bi-substitution into the Nd site of $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ ceramics. Average grain size increased with Bi-substitution. Dielectric constant(${\varepsilon}_r$) increased from 84 to U8, and the temperature coefficient of resonant frequency(${\tau}_f$) decreased from 44 ppm/$^{\circ}C$ to -30 ppm/$^{\circ}C$ when Bi contents increased up to x=0.2 in $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ solid solutions. $BaO.(Nd_{1-x}Bi_x)_2O_3.4TiO_2$ solid solutions with x=0.04~0.08 showed the most superior microwave dielectric properties, those are ${\varepsilon}_r$= 89-92, Q . f = 5855~6091 GHz, and (${\tau}_f$)= -7.5-7.5 ppm/$^{\circ}C$.

• Electrical & Electronic Materials
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• v.9 no.9
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• pp.900-905
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• 1996

We have investigated dielectric properties of low fired ceramics BiNbO$_{4}$ containing 0.05[wt%] V$_{2}$O$_{5}$ and x[wt%l Cr$_{2}$O$_{3}$ (x=0, 0.2, 0.4, 0.8, 1.2). By substituting Cr for Bi, dielectric constant .epsilon.$_{r}$ and quality factor Q.f increased and temperature coefficient of resonant frecquency .tau.$_{f}$ changed to positive value. In the composition of BiNbO$_{4}$+0.05 [Wt%] V$_{2}$O$_{5}$+0.8[wt%]Cr$_{2}$O$_{3}$ sintered at 960[.deg. C], we could obtain microwave dielectric properties of .epsilon.$_{r}$=49, Q.f.simeq.3000[GHz](at 4.8[GHz]), .tau.$_{f}$.simeq.0[ppm/.deg. C]. As the above ceramics can be sintered near 960[.deg. C], it is applicable to multilayer microwave device with Ag conductor.tor.tor.tor.