• Journal of Environmental Health Sciences
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• v.47 no.4
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• pp.330-338
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• 2021

Background: This study was conducted to provide background information for the proper management of radon contamination in apartments using mechanical ventilation facilities in residential environments. Objectives: To this end, this study compared and evaluated changes in radon concentrations based on different operating intensities of mechanical ventilation with or without natural ventilation. Methods: For the continuous measurement of radon concentrations, an RAD7 instrument was installed in four apartments equipped with a ventilation system. The measurements were done for comparison of ventilation types and different ventilation intensities ("high", "middle", "low"). Results: The results confirmed that both mechanical and natural ventilation sufficiently reduced the radon concentration in the apartments. In particular, mechanical ventilation at "high" intensity was the most effective. Natural ventilation combined with mechanical ventilation and then natural ventilation alone were the second and the third most effective, respectively. Conclusions: When using ventilation to reduce indoor radon concentrations, it is most effective to operate mechanical ventilation ("high") or natural ventilation and mechanical ventilation at the same time. In cases where mechanical ventilation is available alone, it is recommended to operate it at a minimum of "middle" intensity.

• Journal of the East Asian Society of Dietary Life
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• v.3 no.2
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• pp.107-119
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• 1993

The objeative of this study was to investigate the possibility of estimation of internal quality by observing visible state of strawberry. Several tests such as color("L", "A", H,V,C), degree of blackred ness, opening state of calyx, vitamin C content, brix degree, acidity, freshness, overall quality, chlorophyll content, and anthocyanin content were performend during circulation at 20$^{\circ}C$. Acidity(R=-0.96), chloroph-yll content(r=-0.99), vitamin C content(r=-0.98), freshness(r=-0.96), and overall quality(-0.99), degree of blackredness(r=0.98) and opening state of calyx(=0.98), color saturation(r=0.99), degree of blackredness(r=0.98) and opening state of calyx(=0.98) increased during circulation at 20$^{\circ}C$. in correlation between visible indicators andd internal qualities, "L" valu and brix degree was r=-0.74, "a" and brix degree was r=0.93 Hue and anthocyanin content was r=0.74, value and chlorophyll content, brix degree were r=-0.91, r=-0.77, chroma and brix degree was r=0.96. The correlations between color saturation and vitamin C content(r=-0.96), chlorophyll content(r=-0.98), freshness(r=-0.98), overall quality(r=-0.94), loss of total polyphenol(0.94) and acidity(r=-0.94) showed high correlation. The correlatiions between degree of blackrednes and vitamin C content(r=-0.99), chlorophyll content(r=-0.94), anthocyanin content(=-0.74), freshness(r=-0.97) overall quality (r=-0.95), loss of total polyphenol(r=0.93) and acidity(r=-0.91) chlorophyll content(r=-0.99), freshness(r=-0.98), overall quality(r=-0.92), loss of total polyphenol(r=0.99) and acidity(r=0.83) showed high correlation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.170-178
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• 2000

Most of manufacturers try to produce the most efficient filter for respirators with the lowest breathing resistance. Filter performance depends on low penetration, i.e., high efficiency (%), and low pressure drop ($mmH_2O$). This study was performed to evaluate performance of respirator filters by quality factor ($q_F$) and suggest the direction for improvement of respirator filters of good quality in Korea. Two mechanical filters, S and K made in Korea, three filtering facepieces, S made in China, C made in Korea and M made in USA, which were widely used in the workplace, were selected and tested efficiency and pressure drop in accordance with flow rate, using with Automated Filter Tester Model 8110 (TSI, USA). The best quality factor within the same respirator filter categories was $0.0672cm^{-1}\;H_2O$ for mechanical filter S, $0.0698cm^{-1}\;H_2O$ for filtering facepiece M at flow rate of 32Lpm. Mechanical filter S would be the best suitable during heavy work since qulity factors decrease less sharply than any others as increased flow rates. It was necessary for mechanical filter S to lower pressure drop without increasing efficiency, but mechanical filter K should be increased efficiency and decreased pressure drop. While filtering facepiece M had the best quality performance of three ones, Sand C should get much higher efficiency and lower pressure for better performance.

• Journal of International Academy of Physical Therapy Research
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• v.10 no.4
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• pp.1907-1913
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• 2019

Background: The prevalence of neck pain and neck dysfunction is high in general population. However, there is little literature on the relationship and factors affecting neck pain and neck dysfunction. Objective: To investigate the correlation between neck and shoulder pain, headaches, neck and shoulder dysfunction, and sleep quality in adults with chronic neck pain, and factors affecting neck pain and neck dysfunction. Design: Cross-sectional study Methods : The sample included 114 subjects, who had complained of chronic neck pain for more 12 weeks. We conducted a Pearson's correlation between neck and shoulder pain, headaches, neck and shoulder dysfunction and sleep quality and a regression analysis of the related variables, thereby analyzing factors affecting neck pain and neck dysfunction. Results : In the present study, in adults with chronic neck pain, neck pain was positively correlated with the Neck Disability Index (NDI), Shoulder Pain and Disability Index (SPADI)-Pain score, and SPADI-Total score (p<.05). The NDI was positively correlated with neck pain, SPADI-Pain score, and SPADI-Total score, as well as with Pittsburgh Sleep Qulity Index(PSQI-K) (p<.05). Among the factors affecting neck pain, shoulder disability as assessed by the SPADI was a significantly associated with neck pain, while shoulder pain and shoulder disability determined by the SPADI were identified as significant variables among the factors affecting neck disability. Conclusion : These results indicated that as neck pain worsened, shoulder pain and neck and shoulder dysfunction also increased, which suggested that shoulder disability affected neck pain. In addition, as the neck dysfunction increased, neck pain and shoulder pain and shoulder dysfunction increased, and sleep quality deteriorated, which suggested that shoulder pain and shoulder disability affected neck disability.

• Anxiety and mood
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• v.12 no.2
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• pp.113-118
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• 2016

Objective : Premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD) is known to reduce the quality of sleep and is associated with various psychiatric disorders. The aim of this study was to investigate the relationship of PMS with depression, sleep qulity and sleep pattern in Korean female adolescents. Methods : Out of 867 high school female students, 400 female subjects were included in this study. All participants completed self-report questionnaires that included demographic variables, shortened premenstrual assessment form (SPAF), patient health questionnaire-9 (PHQ-9), Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), insomnia severity index (ISI) and Korean translation of composite scale (CS). A total of 394 individuals who completed the questionnaires were analyzed. Results : As score of SPAF, 143 subjects was defined PMDD group. They had more prevalence of eveningness, more depressive symptom, poorer sleep quality, and more excessive sleepiness than non-PMDD groups. Although the PMDD groups showed more menstrual dysmenorrhea, no difference was found in bleeding duration and cycle. PMS symptom had correlations with depression, poorer sleep quality and excessive sleepiness during the daytime. There was no difference in sleep duration between two groups, but PMS might have a relationship with eveningness of chronotype. Conclusions : Among Korean female high school students, the PMS might have an association with depression and poor sleep quality, and it might lead to daytime impairment due to excessive sleepiness. An appropriate evaluation of PMS could be helpful in determining the mental health condition of adolescents.

• Food Science and Preservation
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• v.6 no.4
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• pp.380-385
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• 1999

Four cultivar of astringent persimmon(Diospyros kaki L. Cheongdobansi, Sagkoksi, Gojongsi, and Hachiya) were evaluated for quality during 160 days storage in condition of air, 12%CO$_2$+3%CO$_2$, and 16%CO$_2$+ 3%CO$_2$at 0∼2$^{\circ}C$. In the fruits of Cheongdobansi, Sagkoksi, and Gojongsi cultivar, the soluble solids content did not change significantly during storage among treatment, but in the fruits of Hachiya cultivar it decreased during storage in the codition of high CO$_2$concentration. Fruits of Cheongdobansi and Sagkoksi, which were stored in higher CO$_2$concentration, had firmer hardness, less weight loss and decay, showed greater rentention of initial peel color, maintained best qulity than air-stored fruit, but had high tannin contents. And it was necessory to remove astringency for edible fruits.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.240-245
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• 2010

The objective of this study was to determine the effect of different height of drainpipe and growing media soilless cultivated cut rose in container culture. Two experiment were to examine the effect of the drainpipe height and media composition on yield and quality of cut rose, Four different drainpipe height (0, 3, 6, 9 cm) were treated to determine of optimal container type. Yield was the highest at 3 cm drainpipe height, but quality was not significantly affected by drainpipe height. Survival rate of rose was 100%, 100%, 92%, and 92%, respectively. Two different drainpipe height (0, 3 cm) and 7 media composition (pure coir and pelite, and mixed with two media 3 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3 v/v) was treated to determine of media composition related to drainpipe height. The supply of nutrient solution was controlled by the signal of water potential at -5 kPa using frequency domain reflectometry (FDR) sensor in mixed coir with pelite 3 : 1, 1 : 1, 1 : 3 (v/v), respectively. Irrigation frequency reduced in high ratio of coir media and 3 cm height of drainpipe. Quality of cut rose except for flower weight and yield until 2nd harvest was not significantly affected by drainpipe height, but yield after 3rd was higher at 3 cm than 0 cm height of darinpipe. In the media composition, yield and qulity of cut rose was increased at high ratio of coir media.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.311-316
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• 2018

As the lives of people have improved, the demand for improved indoor air quality has increased. Various methods are used to remove biological air pollutants, such as UV/photocatalytic devices and ozone generators. However, these methods have disadvantages such as energy consumption, high corrosivity and toxicity. To overcome these disadvantages, an antibacterial copper filter was fabricated and its antimicrobial activity was then tested against two fungi (P. pinophilum, C. globosum) and one bacteria (S. aureus) Moreover, the ability to remove suspended microorganisms was tested step by step from the chamber stage to the air conditioning system. The results revealed 100% antimicrobial activity after 24 hours for the two fungi, while this value was 99.9% after 18 hours for the bacteria. Moreover, the antibacterial activity was higher when the chamber and air purifier were used than was obtained using a general antibacterial HEPA filter. Also, as a filter for system air conditioner, the antibacterial activity was lowered in offices and hospitals. In conclusion, the copper filter was found to have sufficient antibacterial activity for use as an antibacterial filter; however, further research on its preparation methods and materials is warranted.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.1
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• pp.61-67
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• 2017

This experiment was conducted to obtain information of feed value and fermentative quality of wheat cultivar, 'Taejoong' to confirm availability as a whole crop silage. As a result, the heading date of 'Teajoong' is April 27, and plant height is longer than whole crop barley, 'Youngyang' or whole crop wheat, 'Cheongwoo', spike length are also large, fresh and dry matter yield are also high. In case of feed value, 'Taejoong' had higher crude protein content than whole crop barley, 'Youngyang' or whole crop wheat, 'Cheongwoo', lower NDF and ADF contents, and significantly higher digestible nutrient contents(p<0.05). In case of fermentation qulity, pH of 'Taejoong' was 4.2, and lactic acid content was lower than 'Cheongwoo' silage and significantly higher than 'Youngyang' silage(p<0.05). Acetic acid content was significantly lower than 'Youngyang' and 'Cheongwoo' silage(p<0.01), butyric acid content was significantly lower than that of 'Youngyang' silage (p<0.05). The final Flieg's score showed that 'Taejoong' silage was the best. Also income of 'Taejoong' improved than 'Youngyang' or 'Cheongwoo'. Therefore, 'Taejoong' is considered sufficiently available as whole crop for forage.

• Food Science and Preservation
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• v.6 no.4
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• pp.463-468
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• 1999

The characteristics and quality of Yakju with addition of ginseng powder originated in Choongchungdo were evaluated. At result, pH was decreased at the beginning stage of two stages fermentation and then slowly increased. Total acidity were increased in the cases of all (A), (B) and (C) during the fermentation. (A) group used Nuruk, crude enzyme and powder yeast showed the highest pH of 7.08 and total acidity of 0.84 at the 4th day of fermentation. The alcohol contents of B(21.0%) and C(20.4%) used cultured yeast were higher than A(19.0%) used powder yeast at the 4th day of fermentation. Also, inhibition against alcohol fermentation by ginseng powder wasn't showed and amino nitrogen contents were higher in (A) and (C) with addition of crude enzyme. Free sugar were the highest in (A) used both Nuruk and crude enzyme such as glucose of 599.16, maltose of 129.11mg%. Free amino acids were much more in A(580.02mg%) than in B(527.48mg%) and C(538.74mg%). from the sensory evaluation, desirable color and flavor qulity for 40 ages was (A) and (B) which was used Nuruk, and that for 20 ages was (C) which was used crude enzyme. However the best taste and overall preference was (B) for 20 and 40 ages of all. Therefore to produce high quality Yauju and commercialize, studies of fermentation process in Yakju should proceed later.