• 한국농공학회지
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• 제15권4호
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• pp.3147-3152
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• 1973

The factors to influence the travelling distance of sprayed particles for the medium range nozzle may by the groove depth of swirl plate, the cap slope, the diameter of cap hole, and pressure. 1. This study was conducted to examine Interaction effects among four factors to the travelling distance. The results of this study are summarized as followa; a) Interaction effects among four factors the groove depth(G), cap slope(C), diameter of cap hole(D), and pressure (P), were significant to influence the travelling distance except for $G{\times}P,\;C{\times}D{\times}P\;and\;G{\times}C{\times}D{\times}P$. b) Interaction effects with the pressure were very smaller than interaction effects among the other factors. c) Effect of change of the groove depth of swirl plate on the travelling distance of sprayed particles was generally a linear, the increasing rate of the change was about 0.345, which was very significant. d) Effect of change of cap slope on the travelling distance was generally a linear or a dull quadratic, the increasing rate was very small. e) Main effect of change of cap slope in the medium range nozzle was very smaller than that of the close range nozzle on the travelling distance, which was estimated by the changing of turning radius of flowing course in nozzle. f) Interaction effect between two factors in the medium range nozzle was more significant than that of the close range nozzle on the travelling distance.

• 대한간호학회지
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• 제38권2호
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• pp.238-247
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• 2008

Purpose: The purpose of this study was to measure the level of stress and symptoms of stress (SOS) in soldiers and to investigate the factors that have effects on the symptoms of stress. Methods: Data was collected from soldiers of two military units located in north Kyounggi-Do from August 2 to 9, 2006 by using the survey instruments. Results: This research found that the average values on the level of stress and symptoms of stress were about $2.53{\pm}0.60$ (range 1.00-4.35) and $0.95{\pm}0.55$ (range 0.04-2.83), respectively. The things which affected symptoms of stress, according to this study, were the external factors in the military (${\beta}=.28$, p<.001), role and relation factors (${\beta}=.21$, p<.001), work factors (${\beta}=.15$, p=.01) and passive coping styles (${\beta}=.19$, p<.001). These variables explained 28% (F=36.68, p<.001) of the variance of the total symptoms of stress. Conclusion: This study suggests that soldiers need to under go stress management.

• Bulletin of the Korean Chemical Society
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• 제22권7호
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• pp.703-708
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• 2001

K2NiF4-type organic-based perovskites of the (C4H9NH3)2FexPb1-xCl4 (x=0.00, 0.25, 0.50, and 0.75) system have been synthesized using a low-temperatu re solution method under a flowing argon gas. When stoichiometric butylamine, iron chloride, and lead chloride are mixed, a yellow solution are obtained from slow cooling of 90 to -10 $^{\circ}C.$ The final product is a plate-like yellow crystal. The X-ray crystallographic analysis has been carried out using XRD in the range of $5^{\circ}{\leq}$ 2${\theta}$ ${\leq}80^{\circ}.$ The local symmetry around the absorbing Pb atom of the samples has been determined by the EXAFS spectroscopic study. The crystals assign to orthorhombic system by the XRD analysis. The FT-IR spectra are analyzed in the range of 600 to 3300 cm-1 . DSC and TGA are measured to detect thermal stability between 30 and 300 $^{\circ}C.$ Two endothermic peaks are detected in all samples. The electrical conductivity has been measured using the four-probes technique for the (C4H9NH3)2FexPb1-xCl4 system in 300-460 K. Photoluminescence phenomenon was also investigated at room-temperature.

• 한국산업보건학회지
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• 제20권4호
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• pp.217-224
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• 2010

The purity methods to determine LOD/LOQ using standard deviation of the residual, intercept and blank by IUPAC and ACS describe many of the pitfalls and pose significant challenges to analytical chemists. Therefore, the aim of this study is the development of the simple, easy, convenient and statistically significant method to determine LOD in quantitative analysis of organic solvents by GC. The new approaching method by linearization in the given concentration range used coefficient of variation ; ${\sigma}_{n-1}$/S(standard deviation, ${\sigma}_{n-1}$ and average, S) of sensitivity(Response/concentration). The comparison of results among the purity methods(IUPAC and ACS) and the linearization have been fulfilled the F-test for standard deviations and t-test for LOD range values. The results of F-test and t-test are satisfied within 95 % confidence level, respectably. The LOD values determined by the new procedure are n-Hexane 0.0116 mg/$m^3$, Toluene 0.0807 mg/$m^3$, and o-Xylene 0.0494 mg/$m^3$. Because the standard deviation of the residual, intercept and blank and the slope of calibration curve are not calculated and the new approaching method use the coefficient of variation of sensitivity by linearization, this new method is simple, easy, convenient and statistically significant. In future, many chemical analysts will expect to applicate and routinely use this method in the all quantitative analysis.

• 말소리와 음성과학
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• 제4권4호
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• pp.139-146
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• 2012

This study was designed to examine comfort levels of pitch and loudness with target matching and their effects on electroglottographic (EGG) and acoustic measures. Twelve speakers, six males and six females, were instructed to produce /a/ sustained vowel for three seconds at a comfortable pitch and loudness level without any instruction and with a target matching procedure of either a certain f0 or SPL separately with visual and auditory feedback. The range of pitch for females and males were presented by progressing up and down randomly at intervals of 5Hz from 150 Hz to 310 Hz (total 33 frequency targets) and from 85 Hz to 190 Hz (total 22 frequency targets), respectively. The loudness levels were 65, 75, 85, 95 dB (total of four intensity targets) for both males and females. Subjective estimations of comfortable levels were obtained using a 10-point equal-appearing interval rating scale following each phonation. The results showed that males and females demonstrated similar trends in loudness levels with greatest comfort at 75 dB, whereas pitch comfort ratings showed a greater variability with females having a wider range with target matching. In the comfort levels of individuals, most male and female speakers rated higher comfort at soft, rather than loud phonations. On the other hand, most male speakers perceived highest comfort levels below the comfort pitch levels they phonated under natural conditions. Higher frequency ranges, however, were perceived to be more comfortable than those of natural condition in most female speakers, although the comfortable pitch levels in spontaneous phonations were within the comfort level ranges determined by targeted phonations. When comparing acoustic (%jitter, %shimmer, SNR) and EGG measures (CQ%) between spontaneous comfortable phonations and targeted phonations produced by the same subject at similar f0 and intensity, no significant differences were observed (p>0.05). Thus, target matching procedures may be considered a compatible and alternative method to reduce the variability of comfortable pitch and loudness levels by eliciting consistent comfortable phonations.

• 한국환경보건학회지
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• 제45권2호
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• pp.99-112
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• 2019

Objective: This study aims to analyze the characteristics of airborne radon and thoron level ($Bq/m^3$) generated from household products containing monazites, and estimate the effective doses (mSv/yr). Method: Radon & Thoron detector EQF3220 was used to monitor real-time airborne radon and thoron level ($Bq/m^3$), and their daughters ($Bq/m^3$) were recorded every two hours. Effective doses (mSv/yr) for radon and thoron were estimated according to models developed by International Commission on Radiological Protection (ICRP) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Results: The average levels of radon and thoron were $87.8Bq/m^3$ (range; $20.8-156.3Bq/m^3$) and $1,347.5Bq/m^3$ (range; $4-5,839.7Bq/m^3$), respectively. The average equilibrium factors (F) were 0.23 and 0.007, respectively. The levels of radon progeny were far higher than that thoron. Latex mattress showed the highest F (0.38). The average effective doses were estimated to be ICRP (1.9 mSv/yr) and UNSCER (1.3 mSv/yr) for radon and UNSCEAR (1.6 mSv/yr) for thoron. Conclusions: Our results have far exceeded the allowable effective dose for general population (1 mSv/yr). The government's actions such as the ban of use of consumer products containing monazite and the establishment of surveillance system to evaluate health effects for the people affected should be taken as early as possible.

• 핵의학기술
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• 제14권1호
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• pp.122-126
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• 2010

F-18-FPCIT는 뇌 선조체에 주로 분포된 도파민 운반체에 강한 친화력을 보이며, 이는 파킨슨 씨 병의 진단에 유용한 진단적 정보를 제공한다. 본 연구에서는 iteration과 subset에 따른 영상의 변화를 관찰하고 적정한 iteration과 subset의 범위를 제안해 보고자 한다. 영상의 획득은 ACR 팬텀과 뇌 질환이 없는 정상인의 뇌 영상을 획득하였다. 정상인의 뇌영상은 F-18-FPCIT를 정맥주사 후 3시간째 획득하였으며, iteration과 subset의 조건을 5가지로 구분하여 영상을 재구성하였다. 영상의 분석은 동일한 위치에 같은 크기의 ROI를 그려 평균, 최대, 최소의 SUV를 측정하였고, 이를 바탕으로 표준편차, 변이계수를 계산하였다. 또한 팬텀영상에서는 각 조건별 열소와 냉소의 SUV를 비교하여 어떠한 조건에서 실제와 가장 비슷한 SUV ratio를 재현하는지 조사하였다. 위 실험에서 얻어진 값은 Spearman test를 통해 유의성을 유무를 판별하였다. 따라 SUV는 증가하였고 이러한 추세는 Spearman test에서 유의성을 나타내었다. 표준편차 역시 iteration, subset조건이 증가함에 따라 값의 증가를 보였다. 산출된 값들은 통계적으로 유의하였다. 팬텀 연구에서는 6 iteraions, 16 iterations 에서 실제와 가장 비슷한 SUV ratio를 재현하였다. 하지만 iteration, subset 조건별로 얻어진 SUV ratio들은 통계적으로 유의하지 않았다.

• Journal of Microbiology and Biotechnology
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• 제30권4호
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• pp.615-621
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• 2020

Laccases are multicopper oxidases with important industrial value. In the study, a novel laccase gene (mco) in a Staphylococcus haemolyticus isolate is identified and heterologously expressed in Escherichia coli. Mco shares less than 40% of amino acid sequence identities with the other characterized laccases, exhibiting the maximal activity at pH 4.0 and 60℃ with 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) as a substrate. Additionally, the Mco is tolerant to a wide range of pH, heavy metal ions and many organic solvents, and it has a high decolorization capability toward textile dyes in the absence of redox mediators. The characteristics of the Mco make this laccase potentially useful for industrial applications such as textile finishing. Based on BLASTN results, mco is found to be widely distributed in both the bacterial genome and bacterial plasmids. Its potential role in oxidative defense ability of staphylococci may contribute to the bacterial colonization and survival.

• 기본간호학회지
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• 제15권1호
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• pp.80-88
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• 2008

Purpose: By focusing on immigrant women's problems and considering human rights, resettlement plans and marital-life adaptation, health status is often overlooked. It was examined in this study. Method: The participants were 110 immigrant women who lived in Busan. Data were collected from September to November 2007 using a questionnaire. Results: One of five of the women had been hospitalized for a delivery, about 25% were pregnant, and most (80.9 %) have never had a pap-smear test. The average score for anxiety was 3.0 (${\pm}2.50$) and for depression 2.9 (${\pm}2.71$). Most were in the normal range for blood pressure, body mass index(BMI), blood sugar and urine test. There was a significant difference in level of anxiety according to education (F=3.42, p=.020) and in level of depression according to age (F=4.05, p=.020), number of children(t=-.444, p=.009), financial status (F=3.75, p=.027) and satisfaction with life (F=6.38, p=.002). There were significant differences in BMI according to age (F=7.73, p=.001), native nation (F=18.38, p=.000), period of stay in Korea (F=3.11, p=.049), education (F=3.82, p=.012), number of children (t=-4.26, p=.040). Conclusion: Although the health status of the immigrant women was good, procreative care protocols should be developed to support immigrant women who are pregnant.

• 생명과학회지
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• 제15권4호
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• pp.590-594
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• 2005

황토볼을 담체로 사용하여 혐기조${\rightarrow}$호기조${\rightarrow}$무산소조의 순서로 진행되는 폐수처리 시스템(F-STOP PROCESS)에서 폐수의 조성이 COD 200, 총질소 40 (ppm)정도의 합성폐수를 처리하여 다음과 같은 결론을 얻었다. 총질소 성분의 평균 제거율은 $83.0\%$이였으며, 암모니아성 질소는 평균 제거율이 $84.4\%$이였다. 또한 질산성 질소는 호기조의 평균 질산화율은 $60.2\%$이였는데 유출수의 pH범위가 $4.8\~6.0$인 것을 고려하면 양호한 결과를 보였으며, 무산조의 질산성 질소의 제거율은 $96.3\%$으로 상당히 좋은 결과를 보이고 있다. 최종 방류조의 유출수 COD는 12.8ppm으로 평균 제거율 $93.6\%$이였으며, SS의 경우에는 평균발생량은 7.0ppm이였다. 이러한 결과치는 하수종말처리장(특별대책지역 및 잠실수중보권지역) 기준 및 폐수처리시설(농공단지 오 폐수처리시설 포함) 기준 이내의 기준에 해당하는 영양염류의 수치로 양호한 결과를 보여주었다. 그러나 이러한 결과를 유지하기 위해서는 폐수성상에 따른 시스템 순서의 변경, 비정상상태에서 정상운전에 이르는데 요구되는 시간을 줄이는 것 등이 관건으로 되어 있으며, 향후 이러한 방향으로 보다 연구가 진행되어야할 필요성이 있다.