• 한국환경보건학회지
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• 제21권4호
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• pp.24-31
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• 1995

Gas sensing element, $\alpha-Fe_2O_3$ was synthesized by dehydration, reduction, and oxidation of $\alpha-FeOOH$, which was synthesized with $FeSO_4\cdot 7H_2O$ and NaOH. They were produced as a bulk-type, a thick film-type. Then, their responses and mechanisms of response to the gas of carbon monoxide were studied. The qualities of gas sefising elements are decided by the structure and the relative surface area. In the process of $\alpha-FeOOH$ synthesis, the effects of reaction conditions as the equivalent ratio, on the structure and the relative surface area of gas sensing element were observed. The changes of the structure were measured with XRD, SEM,TG-DTA and BET. The resistance changes of the synthesized gas sensor in the air were measured. The response ratio were also measured for the changes of working temperature and gas concentration. As a result of analysis with XRD, it was confirmed that the the best conditions for the synthesis of $\alpha-FeOOH$ were equivalent ratio 0.65. The thick film-type element of $\gamma-Fe_2O_3$ responded more quickly than the bulk-type did. The structure and the relative surface area of the $\rho-FeOOH$ were confirmed as the important factors deciding gas response charcteristics.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 춘계학술대회논문집
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• pp.3-9
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• 1997

EEG(electroencephalogram) is attempted to determination of human emotion. Ten university students were participated in this study. Ten auditory stimuli were presented for a subject to evoke emotion. Data homogeneity according to brain local area and basic mechanism of relative variation for combinational delta, theta, alpha and beta waves were analyzed. As the result, the local area characterized by factor analysis and the relative variation of alpha-delta wave can be considered as the determinants of human emotion.

• Preventive Nutrition and Food Science
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• 제13권4호
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• pp.292-298
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• 2008

The volatile composition of Kiyomi peel oil cultivated in Korea was studied by using gas chromatography and gas chromatography-mass spectrometry. The peel oil from the Kiyomi fruit was prepared by using a cold-pressing extraction method. Among the 65 components quantified in Kiyomi oil, 25 terpene hydrocarbons and 40 oxygenated compounds were identified, with peak weight percentages measuring 94.5% and 4.9%, respectively. Limonene was the predominant compound (87.5%), followed by myrcene (2.4%), sabinene (0.9%), $\alpha$-pinene (0.8%), $\beta$-sinensal (0.8%), (Z)-$\beta$-farnesene (0.7%), neryl acetate (0.6%), valencene (0.5%), $\alpha$-farnesene (0.5%), and $\alpha$-sinensal (0.5%). A unique characteristic of the volatile profile of the Kiyomi oil was the proportion of aldehydes (2.7%), which resulted from the relative abundance of $\alpha$- and $\beta$-sinensal. Another unique characteristic of the Korean Kiyomi oil was its relative abundance of $\beta$-sinensal, (Z)-$\beta$-farnesene, neryl acetate, valencene, $\alpha$-sinensal and nootkatone. Valencene and $\alpha$- and $\beta$-sinensal were regarded as the influential components of Korean Kiyomi peel oil.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.64-68
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• 1990

The stabilization effect of .alpha.-tocopherol incorporated into liposomal phospholipid membrane was investigated by fluorospectrophotometry and UV-visible spectretarded by the presence of .alpha.-tocopherol in the bilayer of liposomal phospholipid membrane relative to cholesterol-containing liposomes and pure phospholipid liposomes. .alpha.-tocopherol-containing liposomes prolonged the oxidation of liposomes-embedded heme as those of cholesterol-containing liposomes and pure phospholipid liposomes. Thus .alpha.-tocopherol-containing liposomes may be useful for the carrier systems of nutrients and drugs to phospholipid bilayer and stabilized liposomes.

• 대한인간공학회지
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• 제29권2호
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• pp.189-196
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• 2010

The study is to find relative EEG power spectrum and pattern of coherence discriminating attentive and inattentive hand movements. Eight undergraduate students aged from 20 to 27 who had not hand disability participated in this study. Participants were asked to perform visuo-motor task. EEG was measured at C3 in 10~20 international system and four areas orthogonally directed 2.5cm away from C3. Significant result discriminating movement and rest was found through coherence analysis between movement areas or movement area and non-movement area, but was individually different. Because it was anticipated that major factors caused by the differences among individuals were attributed to the attention of the subjects, relative power of alpha and beta bands was identified. As a result, significant relative powers of alpha and beta bands were found in a group of high coherence level, but were not found in a group of low level. Next, participants were divided into two groups according to relative powers of alpha and beta bands. The comparison between two groups was performed. As a result, the coherence of the alpha band in the attentive group was greater than that of the inattentive group. It was found that the coherence of the beta band in the inattentive group was happening. Therefore, individual differences of coherence were influenced by attention. The significant coherence patterns that could discriminate attentive movement and inattentive movement were found.

• 사상체질의학회지
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• 제19권2호
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• pp.113-126
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• 2007

1. Objectives The objective of this study was to measure the differences of EEG changes accoring to emotional stimulus in Sasangin. 2. Methods 44 healthy volunteers(Soyangin 10, Soeumin 14, Taeumin 20) were participated. Sasang Constitution was diagnosed by Sasang specialist. Volunteers watched horror movie as the emotional stimulus. We recorded EEG data during pre-stimulus rest(120sec), during-stimulus(197sec), rest-stimulus(120sec). Power spectral analysis was done and relitive power and ${\alpha}/{\beta}$ ratio were compared among each groups. 3. Results (1) The mean of relative ${\alpha}$ of Taeumin was significantly decreased according to stimulus compared with Soyagnin. (2) Relative ${\alpha}$ of Soeumin was significantly decreased in T3 area according to stimulus compared with Taeumin. (3) Relative ${\beta}$ of Taeumin group was significantly increased in Fp2 area according to stimulus compared with Soeumin. 4) Relative $high-{\beta}$ of Soyangin group was significantly decreased in F3 by the post-stimulus rest compared with Soeumin. (5) ${\alpha}/{\beta}$ ratio of Soeumin was significantly increased according to stimulus compared with other groups. 4. Conclusions Soyangin showed sensitive changes according to the emotional simulus compared with Soeumin and Taeumin. Above results suggest that the emotional characteristics of Sasangin can be measured by objective methods as by EEG.

• 한국세라믹학회지
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• 제34권11호
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• pp.1187-1197
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• 1997

Dry gel composed of primary particles more homogeneous than starting boehmite powder was prepared by dispersing and gelling the boehmite powder. The transformation temperatures of boehmite powder, dry gel seeded with 0, 1, 3, 5 wt% $\alpha$-Al2O3, and ball milled gel were 1192$^{\circ}C$, 1184$^{\circ}C$, 1141$^{\circ}C$, 1119$^{\circ}C$, 1117$^{\circ}C$, and 1106$^{\circ}C$, respectively. Sintering behavior of dry gel without seed was similar to that of boehmite powder, but the sintered density of dry gel was improved as much as 10%~15% than boehmite powder. In the case of dry gel seeded with 5 wt% $\alpha$-Al2O3, sintering behavior was much improved. The relative density of the gel seeded with 5 wt% $\alpha$-Al2O3 was 96% when sintered at 140$0^{\circ}C$ for 1h. On the other hand, ball milling of the non-seeded sol for 48h resulted in the relative density of 97% when sintered at 130$0^{\circ}C$ for 1h. The size and amount of $\alpha$-Al2O3 particles added by ball milling were 0.107 ${\mu}{\textrm}{m}$ and 0.5 wt%.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제30권2호
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• pp.139-154
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• 2023

In this paper we wish to prove some results relating to the growth rates of composite entire and meromorphic functions with their corresponding left and right factors on the basis of their generalized relative order (α, β) and generalized relative lower order (α, β), where α and β are continuous non-negative functions defined on (-∞, +∞).

• 한국안전학회지
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• 제11권2호
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• pp.67-78
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• 1996

Gas sensing element, $\gamma-Fe_2O_3$was synthesized by dehydration, reduction, and oxidation of $$${\gamma}$-FeOOH, which was synthesized with $FeSO_4\;{\cdot}\;7H_2O$ and NaOH. They were produced as a bulk-type, a thick film-type. Then, their responses and mechanisms of response to the gas of liquefied-petroleum were studied. The qualities of gas sensing elements are decided by the structure and the relative surface area. In the process of $\alpha-FeOOH $synthesis, the effects of reaction conditions as the equivalent ratio, on the structure and the relative surface area of gas sensing element were observed. The changes of the structure were measured with XRD, SEM, TG-DTA and BET. The resistance changes of the synthesized gas sensor in the air were measured. The response ratio were also measured for the changes of working temperature and gas concentration. As a result of analysis with XRD, it was confirmed that the the best conditions for the synthesis of $\alpha -FeOOH$ were equivalent ratio 0.65. The thick film-type element of $\gamma-Fe_2O_3$responded more quickly than the bulk-type did. The structure and the relative surface area of the $\alpha-FeOOH $were confirmed as the important factors deciding gas response charcteristics.

• 한국환경보건학회지
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• 제29권2호
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• pp.16-22
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• 2003

BBP (Butyl benzyl phthalate), a widely used plasticizer. can enter the food and environment as consequence of its manufacture, use, and disposal. BBP was found to be developmental and teratogenic or endocrine disrupting chemical in rats. The effects of BBP were investigated in female rats (P) and second generation (F1) via lactations. Sprague-Dawley were given BBP by oral administration at 0, 5, 10, 100, 1000 mg/kg on day 0 to 21 of lactation period. The results were as follows : At maternal findings, there were some significant changes (p<0.05) in relative organ weight, especially liver and uterus weight by BBP administration. In estrous cycle, high treated group was inclined to be proestrus or estrus compared to control group. BBP indues estrous cycle earlier than the control group. At fetal findings, there were some significant changes in relative liver and spleen weight, especially 100, 1000 mg/kg administered groups. The relative weight of ventral prostate was decreased, so it was represent to dose-response tendency. Parent rats (P) were detected monobenzyl phthalate (MBeP) 3.21~5.81 $\mu\textrm{g}$/ml in 100, 1000 mg/kg dose groups. MBeP of male and female fetuses (F1) were detected at the level of 1.21~2.63 $\mu\textrm{g}$/ml of serum. Male serum concentration oi MBeP was higher than the females'. Estrogen receptor $\alpha$ expression by BBP and bisphenol A in uterus and testis of F1 were studied. The ER$\alpha$ expression were increased in F1 male testis and female uterus. F1 male showed distint ER$\alpha$ expression, especially in the combined exposrue. Synergistic ER$\alpha$ expression was found by combined treatment group of BBP and bisphenol A. From the above results, it could be concluded that the effects of dams and F1 by BBP administration during lactation period were estrogenic, and BBP can transfer to F1 via lactation, and make estrogenic at F1 reproductive organs.