• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7C
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• pp.581-586
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• 2010

The holographic data storage system stores multiple data pages by multiplexing. But the inter-page interference(IPI) caused by multiplexing reduces the intensity of the hologram. The simulation of the holographic storage systems has to consider the IPI. Therefore, we introduce a channel modeling that takes care of inter-page interference in the holographic data storage system. We simulate the performance of PRML detection on the hologrpahic data storage system with IPI modeling.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.112.2-112.2
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• 2007

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• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.337-340
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• 2005

Rotating annular disks are widely used in data storage devices such as CDs, DVDs(digital versatile disks), and HDs(hard disks). Higher data transfer rate in data storage disks could not be achieved by polycarbonate disks in the present market. The problem can be solved by applying the fiber-reinforce composite materials to the disks. In this paper, an application of composite materials to rotating disks is proposed to increase the critical speed. Dynamic equation is formulated in order to calculate the natural frequency and critical speed for rotating composite by the Galerkin method. The results show that the radially reinforced disk is more effective in increasing critical speed than the circumferentially reinforced disk.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11b
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• pp.487-493
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• 1996

판(leaf)의 너비가 일정하고 두께가 균일하게 감소하는 두께감소 홀다운스프링집합체(Tapered-Thickness Holddown spring Assembly ; TT-HDS)에서 단순 보 이론과 Castigliano의 정리를 이용하여 TT-HDS의 탄성강성도를 해석적으로 구할 수 있도록 종래에 유도되었던 탄성강성도 평가식을 수정하고 확장하였으며 TT-HDS의 기하학적 설계자료를 이용하여 탄성강성도를 평가하였다. 아울러 ANSYS code 의 접촉요소를 이용하여 TT-HDS을 유한요소 모델링하여 탄성강성도를 수치적으로 평가하였다. 평가 결과 전단력 및 축력이 TT-HDS의 탄성강성도에 미치는 영향은 약 0.09∼0.16%정도로서 TT-HDS의 탄성강성도는 주로 굽힘모우멘트에 의해 지배되고 있음이 확인되었다. 또한 접촉요소로 유한요소 모델링하여 평가한 결과는 확장된 평가식으로 평가한 탄성강성도와 매우 잘 일치하고 있음을 발견하였다.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3252-3259
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• 2023

The influence of hold-down spring (HDS) on the vibration characteristics of core barrel is studied in this paper. First, the vibration characteristics experiment of core barrel was carried out with four type of different hold-down spring. These hold-down springs represent the same hold-down force under different spring stiffness and different hold-down force under the same spring stiffness. And then a new finite element method for researching the influence of hold-down spring on the vibration characteristics of core barrel was presented. This new method could consider the influence of the hold-down force and the spring stiffness at the same time. The results suggest that, the hold-down force and friction have greater influence on the vibration characteristics of core barrel than the spring stiffness, and the influence is nonlinear. The influence of the boundary condition on beam mode is greater than that on shell mode for core barrel.

• Journal of Environmental Health Sciences
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• v.46 no.3
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• pp.285-296
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• 2020

Objective: The objective of this study was to describe the characteristics of exposure to humidifier disinfectants (HDs) and their association with the presence of a person who experienced the adverse health effects in general households in Korea. Methods: During the month of December 2016, a nationwide online survey was conducted on adults over 20 years of age who had experience of using HDs. It provided information on exposure characteristics and the experience of health effects. The final survey respondents consisted of 1,555 people who provided information on themselves and their household members during the use of HD. Exposure characteristics at the household level included average days of HD use per week, average hours of HD use per day, the duration within which one bottle of HD was emptied, average input frequency of HD, amount of HD (cc) per one time used, and active ingredients of HD products (PHMG, CMIT/MIT, PGH, or others). The risk of the presence of a person who experienced adverse health effects in the household was evaluated by estimating odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for monthly income and region using a multiple logistic regression model. Subgroup analyses were conducted for households with a child (≤7 years) and households with a newborn infant during HD use. Results: The level of exposure to HD tended to be higher for households with a child or newborn infant for several variables including average days of HD use per week (P<0.0001) and average hours of HD use per day (P<0.0001). The proportion of households in which there was at least one person who experienced adverse health effects such as rhinitis, asthma, pneumonia, atopy/skin disease, etc. was 20.6% for all households, 25.3% for households with children, and 29.9% for households with newborn infants. The presence of a person who experienced adverse health effects in the household was significantly associated with average hours of HD use per day (P_trend<0.001), duration within which one bottle of HD was emptied (P_trend<0.001), average input frequency of HD (P_trend<0.001), amount of HD per one use (P_trend=0.01), and use of HDs containing PHMG (OR=2.23, 95% CI=1.45-3.43). Similar results were observed in subgroup analyses. Conclusion: Our results suggest that level of exposure to HD tended to be higher for households with a child or newborn infant and that exposure to HD is significantly associated with the presence of a person who experienced adverse health effects in the household.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.386-392
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• 2016

This study investigated the isoflavone content, total phenol content, antioxidant activities (DPPH radical scavenging and oxygen radical absorbance capacity) and ${\beta}$-glucan content of defatted soybean extracts by bioconversion. Soybean was fermented with Lentinula edodes using submerged liquid fermentation system. Defatted soybean powder prepared by hexane (HDS; hexane defatted soybean) and ethanol (EDS; ethanol defatted soybean). The major components of non-fermented HDS (NFHDS) and EDS (NFEDS) were glucoside, such as daidzin, glycitin and genistin. During the bioconversion processing, isoflavone glucoside converted into aglycone such as daidzein, glycitein and genistein. The highest total isoflavone contents of fermented HDS (FHDS) were $2577.96{\mu}g/mL$, and the lowest total isoflavone contents of NFEDS were $428.27{\mu}g/mL$. The highest total phenol contents of fermented EDS (FEDS) was 42.34 mg GAE/g. DPPH radical scavenging and ORAC value were 31.30 to 59.92% and 247.48 to $786.36{\mu}M\;TE/g$ in non-fermented defatted soybean and fermented soybean, respectively. ${\beta}$-Glucan contents were 0.09 to 0.11% in non-fermented defatted soybean and fermented soybean, respectively. These results indicate that fermented soybean could be used as natural antioxidants for the development of functional foods.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.5 no.1
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• pp.83-92
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• 1994

Paroxetine is a potent and selective serotoin re-uptake inhibitor. It is well known as an effective and safe antidepressant and increasingly used for neurotic or non-psychotic depression with anxiety symptoms. The present study assessed antidepressant and antianxiety efficacy and tolerability of paroxetine against placebo in child-adolescent and adult depressive neurosis patients. 232 subjects aged 8-55 years and meeting DSM-III-R criteria for depressive neurosis or dysthymia were divided into 8 subgroups according to their sex and age(8-11 yeard old, 12-17 years old, 18-35 years old and 36-55 years old subgroup in each male and female group). In each subgroup, the randomly assigned half of the patients were treated with paroxetine(10-30mg/day) and the others with placebo for the first 2 weeks in double blind fashion. After 1 week of drug-washout period, paroxetine and placebo groups were crossed over. The depression and anxiety symptoms were assessed with Hamilton Depression Scale(HDS) and Hamilton Anxiety Scale(HAS) at baseline and every 1 week during the trial periods. The levels of reduction in HDS and HAS scores from baseline after 2-week trial were compared between paroxetine- and placebo- treated periods by paired t-test. In all the 8 subgroups, statistically significant differences between paroxetine and placebo were found on the antidepressant efficacy after 2-week treatment. The antidepressant efficacy of paroxetine compared to placebo was most prominent in child and adolescent female groups. On anxiety symptoms, paroxetine was also significantly more effective than placebo. The antianxiety efficacy of paroxetine compared to placebo was most prominent in male and female child groups and young adult female group aged 18-35 years. As for the adverse effects of paroxetine, 3 out of 232 subjects reported mild indigestion and abdominal pain. however, in all the 3 cases, the symptoms improved without reduction of dosage or discontinuation of the drug. In conclusion, paroxetine showed significantly higher antidepressant and antianxiety efficacy compared to placebo in child-adolescent and adult depressive neurosis patients after 2-week treatment. Further trials of paroxetine in depressive neurosis are warranted to elucidate the long-term antidepressant and antianxiety efficacy of paroxetine.

• Progress in Medical Physics
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• v.25 no.2
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• pp.110-115
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• 2014

To compare 2 beam arrangements, circumferential equally angles (EA) beams or partially angles (PA) beams for stereotactic body radiation therapy (SBRT) of primary lung cancer for intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) delivery techniques with respect to target, ipsilateral lung, contralateral lung, and organs-at-risk (OAR) dose-volume metrics, as well as treatment delivery efficiency. Data from 12 patients, four treatment plans were generated per data sets ($IMRT_{EA}$, $IMRT_{PA}$, $VMAT_{EA}$, $VMAT_{PA}$). The prescribed dose (PD) was 60 Gy in 4 fractions to 95% of the planning target volume (PTV) for a 6-MV photon beam. When compared with the IMRT and VMAT treatment plan for 2 beams, conformity index, homogeneity index, high dose spillage, D2 cm (Dmax at a distance ${\geq}2cm$ beyond the PTV), R50 (ratio of volume circumscribed by the 50% isodose line and the PTV), resulted in similar. But Dmax of the Organ at risk (OAR), spinal cord, trachea, resulted in differ between four treatment plans. Especially $HDS_{location}$ showed big difference in 21.63% vs. 26.46%.

• Korean Journal of Food Science and Technology
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• v.48 no.2
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• pp.104-110
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• 2016

In this study, the physicochemical and sensory characteristics of hot water extracts of Codonopsis lanceolata root skin (RS) and root flesh (RF) subjected to different heat treatments were analyzed to determine whether C. lanceolata RS can be used as a tea material. C. lanceolata RS and RF were roasted, hot-air dried (HDS and HDF, respectively), or steamed and hot-air dried (SHDS and SHDF, respectively). The heat-treated samples were extracted with hot water ($90^{\circ}C$) for 90 min. The hot water extracts of RS and RF had lower L-values and higher b-values than the other samples. The RS extracts had significantly higher polyphenol content and DPPH radical scavenging activities than RF samples. In the sensory evaluation, the color acceptability of the teas made from CS, HDS, and SHDS were found to be significantly different from those of the teas made from their respective flesh samples. The results suggest that the hot water extract of the C. lanceolata RS can be utilized as a tea material.