• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.9 no.1
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• pp.38-42
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• 1998

It has been reported that Tonsillectomy ＆ Adenoidectomy(T & A) resulted in the change of voice by structural changes directly to the vocal track. We studied the effect of T & A on the voice of patients comparing the pre-operative to the post-operative voice. It was performed using a Computerized Speech Lab(CSL50) which is currently used as a method for voice analysis. Forty-five patients who had T＆A, aging from 3 to 42 years old, took part in studies and wert evaluated for voice changes and the degree of formant changes of four basic vowels, /a/, /i/, /o/, and /u/. They were evaluated pre-operatively and post-operatively one month later using MDVP, CSL program of CSL50. The results obtained were as follows ; In using MDVP, there were some differences between pre-operative and post-operative shimmer measures within the normal range but other acoustic measures(Fo, jitter, NHR) show no significant differences(p>0.05). F3 of /a/ and /o/ were significantly decreased(p<0.05) and F2, F3 of /i/ were increased(p>0.05) in patients who only had Tonsillectomy in doing CSL spectrogram. For the patients who had T & A, Fl and F3 of /a/, F3 of /i/, Fl, F2 and F3 of /o/ were decreased with significant increase in F1 and F2 of /i/(p<0.05).

• Horticultural Science & Technology
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• v.18 no.6
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• pp.802-807
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• 2000

This study was conducted to propagate the arbuscular mycorrhizal fungi in vitro using the hairy root of carrot transformed by Agrobacterium rhizogenes with Ri t-DNA. Mycorrhizal spores and roots in sudangrass plants were wet-sieved, surface-sterilized and inoculated onto the hairy root of carrot on the Modified Strullu & Romand (MSR) medium. The mycorrhizal spores of Glomus sp. propagated in vitro for 12 weeks was about $50{\mu}m$, and the shapes of spores were round or elliptic. Spores were formed mainly at the middle of the hyphae. Number of mycorrhizal spores propagated using dual culture of the transformed carrot roots and the mycorrhizal inoculum for 12 weeks were about 1,200 per plates.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.2
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• pp.169-175
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• 2014

The age and growth of rabbit fish, Siganus fuscescens were investigated from samples monthly collected in the coast of Jeju island, Korea from February to December 2012. Ages were determined from annuli in otoliths, and annuli were formed in one or two months immediately after spawning once a year. Also, main spawning period was estimated between July and August, thus rings were considered as annual marks. The von Bertalanffy growth equations estimated from a non-linear regression method were $L_t=37.24(1-e^{-0.33(t+1.24)})$ ($R^2=0.92$) for female and $L_t=31.44(1-e^{-0.45(t+1.23)})$ ($R^2=0.90$) for male, and the growth between female and male was different.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05b
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• pp.164-169
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• 2005

A.T.S.의 스위칭 구조와 접점 환경은 주로 아크 전류, 접촉 저항, 아크 시간 등의 불리적 요인이 주로 마모와 특성에 영향을 미치게 된다. 사용되는 접점 재료는 W 또는 WC-Cu 계로 형상과 크기는 전형적인 반구형 구조의 접촉으로 구동이 이루어진다. 따라서 A.T.S.용 접점의 아크 마모 특성 시험을 위한 고려 요인은 이러한 점을 고려하여 시험과 분석이 이루어 졌다. 접점의 마모 특성 실험식으로부터 실제적인 관점에서 보면 제한된 수명을 나타내는 $n_L$을 보장하기 때문에 b<1의 경우가 가장 바람직한 결과로 ATS 접점 시편의 경우 $b{\fallingdotseq}0.99$로 안정된 접점 아크 마모 특성을 갖는 것으로 판단된다. 아크 전압에 대한 모델링과 실험에서 접점 간극 거리 1<0.1mm, 아크전류 i<100A의 시험 조건에 대해 검토한 결과 ATS 접점 시편의 아크전압은 $u_a=10.2V$로 계산되었다. 이 값은 설험적인 값과 상당히 접근하는 특성을 갖는 것으로 나타났으며, 아크에 의한 마모를 억제하기 위해 첨가하는 WC 또는 W의 복합 소결로 인해 아크 에너지가 감소되는 것을 보여준다. 한편 접점의 아크 동작이 분리되는 순간의 동작 시험에서 기존 W(50%wt)-Cu(50%wt) 접점의 값과 비교하면 분리시 아크 전압은 상대적으로 낮아지는 현상은 W강화 첨가량의 증가로 인한 아크 에너지 감소의 제한성을 나타내는 것으로 사료된다.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.120-124
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• 2010

Monometallic, bimetallic and trimetallic particles consisting of different weight compositions of Pt-Pd-Rh over pure alumina wash coats have been synthesized and their catalytic performance on methane conversion was studied from 150 to $600^{\circ}C$. Different catalyst formulations with variable Pt, Pd and Rh contents for bimetallic and trimetallic systems were tried and $Pt_{(1.5)}Rh_{(0.3)}/Al_2O_3$ and $Pt_{(1.0)}Pd_{(1.0)}Rh_{(0.3)}/Al_2O_3$ shows low $T_{50}$ and $T_{90}$ temperatures. Bimetallic and trimetallic particle synergism acts as three way catalysts and therefore, all the catalysts show 100% methane conversion. The effect of supports such as $ZrO_2$ and $TiO_2$ on methane combustion was investigated; from $T_{50}$ and $T_{90}$ results both $Al_2O_3$ and $ZrO_2$ are suitable supports for low temperature methane combustion.

• The Research Journal of the Costume Culture
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• v.26 no.2
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• pp.203-216
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• 2018

This study explores sustainability education in textile and apparel (T&A) programs in U.S. higher education institutions. Specifically, the researchers study whether more courses with sustainability focus are offered in higher-ranked institutions and explore whether sustainability is taught more in specific T&A related subject fields. Content analysis was conducted for 3,200 courses found in online course catalogs or the course information sites of 69 institutions. Institutions were selected from the 2015 rankings of the top 50 fashion design and top 50 fashion merchandising schools in the US on www.fashion-schools.org. All cases were coded by two coders with a Cohen's Kappa score of 97.5%, indicating good interrater reliability. Coded data were analyzed through descriptive statistics, correlation analysis, and t-tests. The findings show that sustainability is being integrated into the curricula and across courses of T&A programs in the U.S. Over half of the institution surveyed offered at least one sustainability embedded course. Higher ranked institutions provided more sustainability-related courses than power-ranked institutions. A natural match between the subject field and specific sustainability theme was observed (e.g., cultural diversity in history/culture and social psychology/education; recycle/reuse in textile science; sustainability in fashion design; social responsibility and ethics in industry/consumer). The need to introduce sustainability in courses holistically is discussed, whereby sustainability within the industry supply chain is examined in a connected way.

• Journal of Oriental Medical Thermology
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• v.3 no.1
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• pp.15-19
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• 2004

Cold hypersensitivity means a condition feeling cold at a temperature when one should not feel so. Cold hypersensitivity has been diagnosed based on the patient's subjective complaints. But these days, cold hypersensitivity can be diagnosed by the help of D.I.T.I.(Digital Infrared Thermal Imaging) This study is designed to verify the validity of diagnosis of cold hypersensitivity by D.I.T.I. Thermographic findings of 100 outpatients who visited the Kangnam Korean Hospital, KyungHee University, Seoul, Korea, from June 2000 to November 2000 were analyzed. The experimental group consisted of 50 patients who complained cold hypersensitivity, and for the control group, 50 patients who did not complain cold hypersensitivity. For the diagnosis of cold hypersensitivity of the hands, thermographic measurements were performed on two pairs of areas(palm-upper arm and back of hand-upper arm). And for that of the feet, other two pairs of areas(anterior thigh-top of the feet and posterior thigh-heel). When the criterion for thermal deviation between the palm and the upper arm was appointed as higher than $0.3^{\circ}C$, the sensitivity was 94.0% and the specificity, 90.0%. And when the criterion for that between the anterior thigh and the top of feet was appointed higher than $2.0^{\circ}C$, the sensitivity was 94.0% and the specificity, 76.0%. Through this study, the diagnostic standard for cold hypersensitivity of hands and feet could be presented.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.168-173
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• 2004

Fretting is a kind of surface degradation mechanism observed in mechanical components and structures. The fretting damage decrease in 50-70% of the plain fatigue strength. This may be observed in aircraft, automobile and nuclear power plant used in special environment and various loading conditions. In the present study, the characteristics of the fretting fatigue are investigated using the two aluminum alloy(Al2024-T3511 and Al7050-T7451). Through the experiment, it is found that the fretting fatigue strength of the Al7050-T7451 alloy decreased about 50% from the plain fatigue strength, while the fretting fatigue strength of the Al2024-T3511 alloy decreased about 45%. The tire track was widely observed in fracture surface area of oblique crack which was induced by contact pressure. These results can be the basic data to the structural integrity evaluation of aluminum alloy subjected to fretting damage.

• Korean Journal of Materials Research
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• v.15 no.12
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• pp.751-755
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• 2005

Fibrous $Al_2O_3-(m-ZrO_2)/t-ZrO_2$ composites having core/shell structure were fabricated by multi-extrusion process. The effect o volume fraction between core ($Al_2O_3-(m-ZrO_2)$) and shell ($t-ZrO_2$ was investigated to understand the relationship between microstructure and material properites, in which the volume fractions of core and shell were varied as 40:60, 50:50 and 60:40. The material properties o hardness and bending strength were increased as the volume fraction of core was increased, and their maximum values were about 1320 Hv and 750MPa, respectively. However, as the volume fraction of core increased, the values of relative density and fracture toughness were decreased from 97.1 to $96.5\%$ and from $6.5MPa{\cdot}m^{1/2}$ to $5.7MPa{\cdot}m^{1/2}$, respectively.

• Journal of the Korean Home Economics Association
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• v.50 no.2
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• pp.75-84
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• 2012

The purpose of this study was to examine the relationship between infants' turn-taking and vocabulary development during a one-year longitudinal study. Participants of this study included 46 infants who participated in both of the 1st and the 2nd tests. The infants' turn-taking frequencies were observed during mother-infant's free play for 10 minutes. The infants' vocabulary was investigated with MCDI-K for the 1st test and PRES for the 2nd test. The collected data were analyzed using both t-test and Pearson's correlation. The research results were as follows: First, the turn-taking frequencies and vocabulary of infants increased with age groups. Second, there was positive relationship between the turn-taking and the receptive vocabulary in group A at T1. Third, there were significant differences in receptive vocabulary at T1 and expressive vocabulary at T2 among group A according to the infants' turn-taking levels.