• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.8 no.1
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• pp.44-48
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• 1997

Anatomic and physiological changes of the larynx with advancing age result in morphologic changes of the vocal fold and reduced control of the phonatory mechanism in elderly individuals and are reflected in increased unstability of fundamental frequency (Fo). The purpose of this study is to increase current understanding of acoustic and stroboscopic characteristics of normal elderly persons voices. First, phonated /a/ vowel productions by 40 normal adults (20 to 40 years, 20 men and 20 women) and 40 normal elderly persons (60 to 80 years,20 men and 20 women) were analyzed, using CSL (model 4300B) acoustic analysis software, to obtain acoustic measures related to fundamental frequency stability nd vocal resonance characteristics. Second, stroboscopic images of the vocal fold behavior in all subjects were analyzed by experienced specialists. In the men, fundamental frequency variation (vFe) (p＜0.01), jitter. (p＜0.05), and shimmer (p＜0.05) for the older group were significantly higher than the value for the adult group. In the stroboscopic findings, edema of vocal fold had a significant finding in aged men (15%). In the women, vFo (p＜0.05), jitter (p＜0.05), and noise to harmonic ratio (NHR) (p＜0.05) for the older group were significantly higher than the value for e adult group and first formant frequency (F1) (p＜0.01) and second formant frequency (F2) (p＜0.01) for. the older group were significantly lower than the value for the adult group. In the stroboscopic findings, vocal fold atrophy had a significant finding in aged women (25%). Frequency stability, as reflected by vFo, jitter, shimmer, and NHR, decreases with advancing age in men and women and spectral analysis of phonated /a/ vowel productions reveals the lowering of the frequency of F1 and second F2 with advancing age, especially in aged women. Change in the mass of vocal folds, due to atrophy or edema, is considered to be the greatest factor in these acoustic changes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.3
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• pp.173-176
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• 2020

This study focuses on a pillar in which is implanted a P-type maneuver under a P base. This structure is called a super junction structure. By inserting the pillar, the electric field concentrated on the P base is shared by the pillar, so the columns can be dispersed while maintaining a high breakdown voltage. Ten pillars were generated during the multi epitaxial process. The interval between pillars is varied to optimize the electric field to be concentrated on the pillar at a threshold voltage of 6 V, a yield voltage of 4,500 V, and an on-state voltage drop of 3.8 V. The density of the filler gradually decreased when the interval was extended by implanting a filler with the same density. The results confirmed that the size of the depletion layer between the filler and the N-epitaxy layer was reduced, and the current flowing along the N-epitaxy layer was increased. As the interval between the fillers decreased, the cost of the epitaxial process also decreased. However, it is possible to confirm the trade-off relationship that deteriorated the electrical characteristics and efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.7
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• pp.3048-3056
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• 2012

The purpose of this study was to investigate VHI, V-RQOL, and vocal characteristics of a teacher and singer. 56 subjects were participated in this study (20 subjects are a teacher with vocal nodule, 20 subjects are a singer with vocal nodule, and 16 subjects are normal speakers). All subjects completed the VHI, V-RQOL, and vocal characteristics were measured using CSL 4500(Kay Pentax. USA). 21 subjects completed the VHI, V-RQOL, and vocal evaluation using CSL 4500 twice to assess test-retest reliability. A statistical analysis was performed using the Statistical Package for Social Sciences 18.0 (SPSS Inc, Chicago, IL). The VHI and V-RQOL showed that the teacher and singer group were significantly higher than those of the control group in functional, physical and emotional aspects(p<0.05). the acoustic analysis using CSL 4500 showed the teacher and singer group were significantly higher than those of the the control group in fundamental frequency related variables, fundamental perturbation related variables, amplitude perturbation related variables, noise related variable, and tremor related variables(p<0.05). Conclusionally, the teacher and singer group recognized their voice problems as a serious physico-functional aspects.

• Transactions on Electrical and Electronic Materials
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• v.7 no.1
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• pp.1-6
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• 2006

Hot carrier degradation and roll off characteristics of threshold voltage ($V_{t1}$) on NMOSFETs as I/O transistor are studied as a function of Lightly Doped Drain (LDD) structures. Pocket dose and the combination of Phosphorus (P) and Arsenic (As) dose are applied to control $V_{t1}$ roll off down to the $10\%$ gate length margin. It was seen that the relationship between $V_{t1}$ roll off characteristic and substrate current depends on P dopant dose. For the first time, we found that the n-p-n transistor triggering voltage ($V_{t1}$) depends on drain current, and both $I_{t2}$ and snapback holding voltage ($V_{sp}$) depend on the substrate current by characterization with a transmission line pulse generator. Also it was found that the improved lifetime for hot carrier stress could be obtained by controlling the P dose as loosing the $V_{t1}$ roll off margin. This study suggests that the trade-off characteristic between gate length margin and channel hot carrier (CHC) lifetime in NMOSFETs should be determined by considering Electrostatic Discharge (ESD) characteristic.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.1
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• pp.33-38
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• 2012

An in-plane thermoelectric sensor was processed on a glass substrate by evaporation of the n-type Bi-Te and p-type Sb-Te thin films, and its sensing characteristics were evaluated. The n-type Bi-Te thins film used to fabricate the inplane sensor exhibited a Seebeck coefficient of -165 ${\mu}V$/K and a power factor of $80{\times}10^{-4}W/K^2-m$. The p-type Sb-Te thin film used to fabricate the in-plane sensor exhibited a Seebeck coefficient of 142 ${\mu}V$/K and a power factor of $51.7{\times}10^{-4}W/K^2-m$. The in-plane thermoelectric sensor consisting of 15 pairs of the n-type Bi-Te and the p-type Sb-Te evaporated thin films exhibited a sensitivity of 2.8 mV/K.

• Electrical & Electronic Materials
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• v.5 no.3
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• pp.320-327
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• 1992

Twin-tub CMOS 공정에 의해 제작된 서브마이크로미터 채널길이를 갖는 n채널 및 p채널 MOSFET의 특성을 고찰하였다. n채널 및 p채널 영역에서의 불순물 프로파일과 채널 이온주입 조건에 따른 문턱전압의 의존성 및 퍼텐셜 분포를 SUPREM-II와 MINIMOS 4.0을 사용하여 시뮬레이션하였다. 문턱전압 조정을 위한 counter-doped 보론 이온주입에 의해 p채널 MOSFET는 표면에서 대략 0.15.mu.m의 깊이에서 매몰채널이 형성되었다. 각 소자의 측정 결과, 3.3[V] 구동을 위한 충분한 여유를 갖는 양호한 드레인 포화 특성과 0.2[V]이하의 문턱전압 shift를 갖는 최소화된 짧은 채널 효과, 10[V]이상의 높은 펀치쓰루 전압과 브레이크다운 전압, 낮은 subthreshold 값을 얻었다.

• Solar Energy
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• v.6 no.2
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• pp.70-75
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• 1986

The fabrication procedure and characteristics of $Ta_2O_5/Al/SiO_2/p-Si$ MIS solar cells forming a fine grating pattern of aluminum evaporated on to p-type silicon crystal are discribed. The proper temperature for oxide growing of these cells was found to be about $450^{\circ}C$ for 20 minutes with oxygen flow. The conversion efficiency increased about 3% after $750{\AA}$ thickness of tantalium silica film spin on anti-reflective coating. The best results showed that $V_{oc}=0.545V,\;J_{sc}=34mA$ and F.F = 0.65, which represent that the conversion efficiency is 12%.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.347-349
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• 1999

We have fabricated insulating thin films using p-hexadecoxyphenol(p-Hp) that was formed phenol-formaldehyde resin of crosslinked structure from reaction with formaldehyde by LB technique. For fabricated MIM device, the possibility for insulating layers of electronic were investigated by electrical properties of their LB films according to crosslinking of LB films current-voltage (I-V) properties and frequency-capacitance (C-F) characteristics. We have provided evidence for the high insulating performance of phenol-formaldehyde thin films by the LB method. Conductivity of their LB films was as follows: pure water > 1 % aq. Formaldehyde > heat treatment, in the current-voltage (I-V) characteristics. It is demonstrated that insulation properties of crosslinked p-HP LB films were improved. In capacitance-frequency properties, the heat-treated p-HP LB films for crosslinking showed a low relative dielectric constant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.128-132
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• 1983

The water relations parameters such as original osmotic pressure $(\Pi_0)$, osmotic pressure $(\Pi_p)$, at the incipient plasmolysis, the volume of osmotic water $(V_o)$ at the full turgor, the relative water content $(RWC^*)$ at the incipient plasmolysis, the volume of osmotic water$(V_p)$ at the incipient plasmolysis, the volume of symplasmic and apoplastic water$(w_s)$ at the maximum turgor, $V_pV_o, \; V_oW_s, \; W_sD_w, \; V_oF_w$ and the elastic modulus were measured through the pressure chamber (DIK-PC-40 Model) technique with the Williams and Geumgangdaerip soybean cultivar shoots. The original osmotic pressure$(\P $i_{0}$ )$, of the both cultivars shoots were appeared insignificant differences as 8.1 bar and 7.8 bar respectively. The osmotic pressure($\pi$$_{p}$ ) at the incipient plasmolysis was 9.0 bar in Williams and 10.4 bar in Geumgangdaerip. The relative water content(RW $C^{*}$) at the incipient plasmolysis was 86.0 per cent in Geumgangdaerip and 92.6 per cent in Williams. The ratio of volume of osmotic water( $V_{p}$ ) at the incipient plasmolysis to total symplasmic water$(V_o)$ , i.e., $V_p/V_o$ was 83.4 per cent in Geumgangdaerip and 90.4 per cent in Williams. The elastic modulus of Geumgangdaerip shoots showed higher value than Williams$(8.5 $\times$ 10^2bar)$ as $1.6 \times10^5$ bar.r.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.550-555
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• 1997

Vibrio cholerae non-O1 (V. cholerae non-O1) was previously called nonagglutinable or noncholera vibrios, since it fails to react with polyvalent O1 antisera. This organism is biochemically and genetically indistinguishable from V. cholerae O1 except serological difference. V. cholerae non-O1 strains are often detected in the environment including bays, estuaries, and fresh water, and also found in food. Therefore it is designated food borne bacterium in Japan. However, research papers on V. cholerae non-O1 are very rare in Korea. In order to investigate bacteriological characteristics of V. cholerae non-O1, we isolated V. cholerae non-O1 from the environmental sea water. Among the isolated V. cholerae non-O1 strains, we selected the strain which had the most strong hemolytic activity, named as V. cholerae non-O1 FM-3. The optimum growth conditions of V. cholerae non-O1 FM-3 were $37^{\circ}C$ and pH 8.5 in BHI broth (containing $0.5\%$ sodium chloride), and it grew better than V. cholerae non-O1 ATCC 25872. But both were not able to grow in BHI broth added $5.0\%$ of sodium chloride or adjusted to pH 5.0. According to the experimental results on the susceptibility test against various antibiotics, there were no significant differences between the isolated strain and reference strain (V. cholerae non-O1 ATCC 25872). Most of the antibiotics examined had bacteriostatic action against V. cholerae non-O1 FM-3 while vancomycin, oxacillin, colistin, polymyxin B, and sulfadiazine had no bacteriostatic activity.