• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.12
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• pp.56-63
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• 1994

The effects of sulfur treatments on the barrier heithts of Schottky contacts and the interface-state density of metal-insulator-semiconductor (MIS) capacitors on InP have been investigated. Schottky contacts were formed by the evaporation of Al, Au, and Pt on n-InP substrate before and after (NH$_{4}$)$_{2}$S$_{x}$ treatments, respectively. The barrier height of InP Schottky contacts was measured by their current-voltage (I-V) and capacitance-voltage (C_V) characteristics. We observed that the barrier heights of Schottky contacks on bare InP were 0.35~0.45 eV nearly independent of the metal work function, which is known to be due to the surface Fermi level pinning. In the case of sulfur-treated Au/InP ar Pt/InP Schottky diodes, However, the barrier heights were not only increased above 0.7 eV but also highly dependent on the metal work function. We have also investigated effects of (NH$_{4}$)$_{2}$S$_{x}$ treatments on the distribution of interface states in Si$_{3}$N$_{4}$InP MIS diodes where Si$_{3}$N$_{4}$ was provided by plasma enhanced chemical vapor deposition (PECVD). The typical value of interface-state density extracted feom 1 MHz C-V curve of sulfur-treated SiN$_{x}$/InP MIS diodes was found to be the order of 5${\times}10^{10}cm^{2}eV^{1}$. This value is much lower than that of MiS diodes made on bare InP surface. It is certain, therefore, that the (NH$_{4}$)$_{2}$S$_{x}$ treatment is a very powerful tool to enhance the barrier heights of Au/n-InP and Pt/n-InP Schottky contacts and to reduce the density of interface states in SiN$_{x}$/InP MIS diode.

• Nonlinear Functional Analysis and Applications
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• v.27 no.2
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• pp.249-259
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• 2022

Let 𝓐 be a unital C^*-algebra. Then it follows that $\sum\limits_{i=1}^{n}(a_ia^*_i)^{\frac{1}{2}}{\leq}\sqrt{n}\(\sum\limits_{i=1}^{n}a_ia^*_i\)^{\frac{1}{2}}$, ∀n ∈ ℕ, ∀a₁, …, a_n ∈ 𝓐. By modifications of arguments of Botelho-Andrade, Casazza, Cheng, and Tran given in 2019, for certain n-tuple x = (a₁, …, a_n) ∈ 𝓐ⁿ, we give a method to compute a positive element c_x in the C^*-algebra 𝓐 such that the equality $$\sum\limits_{i=1}^{n}(a_ia^*_i)^{\frac{1}{2}}=c_x\sqrt{n}\(\sum\limits_{i=1}^{n}a_ia^*_i\)^{\frac{1}{2}}$$ holds. We give an application for the integral of Kasparov. We also derive a formula for the exact constant for the continuous ℓ₁ - ℓ₂ inequality.

• Journal of Ginseng Research
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• v.39 no.2
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• pp.169-177
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• 2015

Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.

• Journal of the Korean Vacuum Society
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• v.12 no.4
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• pp.257-262
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• 2003

The structure and optical properties of n-type and p-type porous silicon (PS) prepared by the chemical etching in the light and the dark, respectively, are reported in this paper. Microstructural features of the samples are mainly investigated by SEM, AFM XRDGI techniques. Also, their optical properties are investigated by photoluminescence (PL) and Fourier transform infrared absorption measurements. In the n-type PS, the room temperature photoluminescence is observed in a visible range from 500 nm to 650 nm in contrast to that in the blue region (400∼650 nm) in p-type PS. Further, semi-transparent Cu films in thickness range of ∼40 nm are deposited by rf-magnetron sputtering on PS to investigate the I-V characteristics of the samples.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.31-31
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• 2009

PECVD를 이용하여 제조된 미세결정질 p-i-n 실리콘 박막 태양전지에서, p 층은 태양전지의 윈도우 역할 및 그 위에 증착될 i ${\mu}c-Si:H$ 층의 'seed'층 역할을 수행하기 때문에, p층의 구조적 및 전기적, 광학적 특성은 태양전지의 전체 성능에 큰 영향을 미칠 수 있다. 본 연구에서는 $SiH_4$ 농도를 변화시켜 각기 다른 결정 특성을 갖는 p ${\mu}c-Si:H$층을 제조하고 그 위에 i ${\mu}c-Si:H$ 층을 증착하여 p층의 결정 특성변화와 그에 따른 i ${\mu}c-Si:H$ 층 및 'superstrate' p-i-n 미세결정질 실리콘 박막 태양전지의 특성 변화를 조사하였다. P층의 경우, $SiH_4$ 농도가 증가함에 따라 결정분율 (Xc)이 감소하여 비정질화되었으며 그에 따라 dark conductivity가 감소하는 경향을 나타내었다. 각기 다른 결정분율을 가지는 p 'seed' 층 위에 증착된 태양전지는, p 'seed' 층의 결정분율이 증가함에 따라 개방전압, 곡선인자, 변환효율이 경향적으로 감소하였다. 이는 p 층 결정분율 변화에 따른 p/i 계면특성 저하 및 그 위에 증착되는 i ${\mu}c-Si:H$ 층의 결함밀도 증가 등에 따른 태양전지 특성 감소 때문인 것으로 판단되며, 이를 분석하기 위하여 i ${\mu}c-Si:H$ 층의 전기적, 구조적 특성 분석 및 태양전지의 dark I-V 특성 등을 분석하고자 한다.

• Communications of the Korean Mathematical Society
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• v.39 no.2
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• pp.331-343
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• 2024

Let ℜ be a *-algebra with unity I and a nontrivial projection P₁. In this paper, we show that under certain restrictions if a map ψ : ℜ → ℜ satisfies $$\Psi(S_1{\diamond}S_2{\cdot}{\cdot}{\cdot}{\diamond}S_{n-1}{\bullet}S_n)=\sum_{k=1}^nS_1{\diamond}S_2{\diamond}{\cdot}{\cdot}{\cdot}{\diamond}S_{k-1}{\diamond}{\Psi}(S_k){\diamond}S_{k+1}{\diamond}{\cdot}{\cdot}{\cdot}{\diamond}S_{n-1}{\bullet}S_n$$ for all S_n-2, S_n-1, S_n ∈ ℜ and S_i = I for all i ∈ {1, 2, . . . , n - 3}, where n ≥ 3, then ψ is an additive *-derivation.

• Journal of Oral Medicine and Pain
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• v.36 no.1
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• pp.25-37
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• 2011

The purpose of this study is to investigate the relationship between personality type and symptoms and contributing factors of temporomandibular disorders. 199 college students completed the MBTI(Myers-Briggs Type Indicator) and a questionnaire and collected data were analyzed by SAS 9.2 program. The obtained results were as follows : 1. The prevalence of symptoms of temporomandibular disorders and mean scales of positive answers of contributing factors appeared to be higher in I type, S type, T type, P type than in E type, N type, F type, J type. 2. ISTP and ISFP among 16 types of personality seemed to have higher prevalence of symptoms and contributing factors of temporomandibular disorders than other types of personality. 3. Symptom of TMJ pain during mouth opening seemed to occur more frequently in I type, S type, F type, J type than in E type, N type, T type, P type. 4. Contributing factors including clenching and stressful state occurred significantly more frequently in I type than E type. Gum chewing habit occurred significantly more frequently in E type than in I type. 5. Unilateral chewing habit occurred significantly more frequently in J type than in P type. 6. Nervous or sensitive persons had significantly higher mean scales of positive answers of subjective symptoms than relaxed or general persons. 7. General persons had significantly lower mean scales of positive answers of contributing factors than nervous, sensitive and relaxed persons. In conclusion, these results show that there is the relationship between personality and temporomandibular disorders and patient education and counselling considering personality type may contribute to treating patients with temporomandibular disorders.

• Journal of applied mathematics & informatics
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• v.20 no.1_2
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• pp.75-96
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• 2006

Let m, n be positive integers. We denote by R(m,n) (respectively P(m,n)) the class of all groups G such that, for every n subsets $X_1,X_2\ldots,X_n$, of size m of G there exits a non-identity permutation $\sigma$ such that $X_1X_2{\cdots}X_n{\cap}X_{\sigma(1)}X_{/sigma(2)}{\cdots}X_{/sigma(n)}\neq\phi$ (respectively $X_1X_2{\cdots}X_n=X_{/sigma(1)}X_{\sigma(2)}{\cdots}X_{\sigma(n)}$). Let G be a non-abelian group. In this paper we prove that (i) $G{\in}P$(2,3) if and only if G isomorphic to $S_3$, where $S_n$ is the symmetric group on n letters. (ii) $G{\in}R$(2, 2) if and only if ${\mid}G{\mid}\geq8$. (iii) If G is finite, then $G{\in}R$(3, 2) if and only if ${\mid}G{\mid}\geq14$ or G is isomorphic to one of the following: SmallGroup(16, i), $i\in$ {3, 4, 6, 11, 12, 13}, SmallGroup(32, 49), SmallGroup(32, 50), where SmallGroup(m, n) is the nth group of order m in the GAP [13] library.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.816-818
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• 2014

Gas target chamber has been developed for producing $^{123}I$ which is radiopharmaceuticals for diagnosis of thyroid cancer, and modeled how to occur nuclear reaction between chamber and $^{124}Xe$ with energy 30MeV inside the gas target chamber by using the MCNPX. The beam energy was lost as the beam spread when beam hit inside the gas target chamber. The cooling water was used not to change the gas target chamber as loss of energy transfer to the thermal energy. Spiral cooling line was designed for cooling the target chamber efficiently. By using the c30 cyclotron, $^{124}Xe(p,2n)$, $^{124}Xe(p,n)$, $^{124}Xe(p,pn)$ nuclear reactions were studied. In this study, we predict the production yield.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.3
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• pp.27-37
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• 2018

PURPOSE: The purpose of this study was to investigate and evaluate muscle activity and foot pressure during gait, and isokinetic strength and balance in persons with functional ankle instability (FAI). METHODS: Nine healthy subjects (CON, n=9) without FAI and 11 patients (FAI, n=11) with FAI participated in the study after having been screened with an ankle instability instrument and a balance error scoring system. In addition, FAI was classified as non-involved (FAI-N) or involved (FAI-I), and CON was classified as dominant or non-dominant. All subjects were evaluated for isokinetic strength (plantar flexion, dorsiflexion, inversion and eversion of $30^{\circ}/sec$ and $60^{\circ}/sec$), balance (static and dynamic), muscle activity (tibialis anterior, peroneus longus and gastrocnemius) and foot pressure (static and dynamic) during gait. RESULTS: Results showed that plantar flexion (p<.05), dorsiflexion (p<.05), inversion (p<.01) and eversion (p<.00) of $60^{\circ}/sec$ were significantly decreased in FAI-I compared to those in FAI-N and CON. C 90 of static balance with eyes open (p<.01) and closed (p<.00) were significantly increased in FAI compared to those in CON. Forward position of dynamic balance (p<.01) was significantly decreased in FAI compared to that in CON. Gastrocnemius and peroneus longus of dynamic muscle activity (p<.01), left and right weight distribution of static foot pressure (p<.00) and pressure distribution of dynamic foot pressure (p<.00) were significantly decreased in FAI-I compared to those in FAI-N. CONCLUSION: We demonstrated that ankle strength, balance, muscle activity and foot pressure were significantly correlated with FAI.