• Journal of Korean Society for Atmospheric Environment
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• v.24 no.1
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• pp.91-99
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• 2008

A multilayer tower-type photoreactor, in which $TiO_2$-coated glass-tubes were installed, was used to measure the vapor-phase BTEX removal efficiencies by ozone oxidation ($O_3$/UV), photocatalytic oxidation ($TiO_2$/UV) and the combination of ozone and photocatalytic oxidation ($O_3/TiO_2$/UV) process, respectively. The experiments were conducted under various relative humidities, temperatures, ozone concentrations, gas flow rates and BTEX concentrations. As a result, the BTEX removal efficiency and the oxidation rate by $O_3/TiO_2$/UV system were highest, compared to $O_3$/UV and $TiO_2$/UV system. The $O_3/TiO_2$/UV system accelerated the low oxidation rate of low-concentration organic compounds and removed organic compounds to a large extent in a fixed volume of reactor in a short time. Therefore, $O_3/TiO_2$/UV system as a superimposed oxidation technology was developed to efficiently and economically treat refractory VOCs. Also, this study demonstrated feasibility of a technology to scale up a photoreactor from lab-scale to pilot-scale, which uses (i) a separated light-source chamber and a light distribution system, (ii) catalyst fixing to glass-tube media, and (iii) unit connection in series and/or parallel. The experimental results from $O_3/TiO_2$/UV system showed that (i) the highest BTEX removal efficiencies were obtained under relative humidity ranging from 50 to 55% and temperature ranging from 40 to $50^{\circ}C$, and (ii) the removal efficiencies linearly increased with ozone dosage and decreased with gas flow rate. When applying Langmuir-Hinshelwood model to $TiO_2$/UV and $O_3/TiO_2$/UV system, reaction rate constant for $O_3/TiO_2$/UV system was larger than that for $TiO_2$/UV system, however, it was found that adsorption constant for $O_3/TiO_2$/UV system was smaller than that for $TiO_2$/UV system due to competitive adsorption between organics and ozone.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.3
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• pp.517-534
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• 1997

It has been held that excessive mechanical forces to the osseous and soft tissues of the TMJ result in joint dysfunction. Understanding the stress pattern on TMJ is very important in TMJ research. But, it is very difficult to measure directly the biomechanical stress distribution in the TMJ when the mandible is loaded. Therefore, stress distribution in the TMJ during functional movement was studied through animal experiment or mathematical model. It was observed and compared the stress distribution occuring in the working and balancing condyle when lower right canine, lower right first molar and lower right second molar were clenched by the three dimensional finite element analysis. Also, stress distribution in the working and balancing condyles were observed and compared when $20^{\circ}$ forward and buccal bite forces were applied to the first molar. The results were as follows : 1. Stress distribution in the condyles during unilateral clenching of the first molar, second molar, canine showed no difference. In the working condyle, tensile force was concentrated on the lateral aspect of the condylar articular surface and condylar neck. And compressive force was concentrated on the anteromedial and lateral aspect of condyle. In the balancing condyle, tensile and compressive forces were concentrated on the lateral aspect of the condylar articular surface and stress transmission to the temporal bone was not observed. 2. When lateral forces were applied to the first molar, tensile forces were concentrated on the medial aspect of the condylar neck and condylar posterior surface in working and balancing condyle. Compressive force was concentrated on the anteromedial and lateral surface of the condyle and stress transmission to the temporal bone was not observed. 3. During unilateral clenching, stress in the working condyle decreased as the occlusal load moved posteriorly while the stress in the balancing condyle increased. when lateral force was applied to first molar, the incremental amount of stress was greater than vertical load. 4. During unilateral clenching, the average balancing/working condyle stress ratio was 2.52. There was a greater concentration of stress in the balancing condyle. The ratio increased as the occlusal load moved posteriorly and decreased considerably when lateral forces were applied to the first molar.

• Korean Journal of Community Nutrition
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• v.13 no.3
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• pp.323-333
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• 2008

The aim of this study was to measure and compare nutrient intake, anthropometric measurements and serum indices by percent body fat as one of the index of obesity degree in female college students. Additionally we attempted to investigate percentile distribution of fat free mass index (FFMI) and fat mass index (FMI) for developing reference values for these two parameters. The subjects were 91 female college students who were classified to 4 groups according to the percentile of percent body fat (Group1: 25 th < percentile of percent body fat, Group 2 : 25 th ${\le}$ percentile of percent body fat < 50 th, Group 3 : 50 th ${\le}$ percentile of percent body fat < 75 th, Group 4 : percentile of percent body fat ${\ge}$ 75 th). The mean percent body fat and body mass index were 28.2%, $20.5 kg/m^2$ respectively. The mean energy intake was 1707 kcal(81% of KDRIs) and vitamin C, folate, Ca and Zn intake were 73.9%, 54.7%, 79.6%, 97.5% of KDRIs respectively. Most nutrient intake (energy, carbohydrate, cholesterol, fatty acid, Ca, Fe) of G4 was lower than that of G1, G2 and G3. Serum HDL-cholesterol concentration was significantly lower in G4 than G1, G2, G3 and it tended to increase as percent body fat decreased. LDL/HDL, A1 of G4 were significantly the highest among the 4 groups and increased as percent body fat increased. The mean fat free mass index and fat mass index were $14.5 kg/m^2$, $6.0 kg/m^2$ respectively. The criteria of sarcopenic obesity which has been defined as under 25 th percentile of FFMI and below 75 th percentile of FMI were shown $12.8 kg/m^2$, $8.2 kg/m^2$ respectively in this study. In conclusion, we should continue to more systematically research on the studies of new obesity measurement which includes FFMI and FMI as one of the variables. And the public education for weight control that emphasizes both the understanding of body composition and the importance of nutrition balance is also required.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.6
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• pp.1149-1158
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• 2000

A radioisotope tracer experiment was carried out in the submerged fixed bioreactor of a dye wastewater treatment facility to evaluate the flow behaviors in the 6 compartments of the reactor and to find any possible factors which may affect to the efficiency of the process. Approximately 20mCi of $^{131}I$ was injected into the system as a tracer and 8 radiation detectors were placed in the 6 compartments and at the inlet and the outlet of the system to measure the change of the tracer concentration with time. Using the Perfect Mixers in Series Model the measured data were analyzed to calculate the mean residence time and the characteristic parameters of the flow in the system. The mean residence time of the system was calculated as 17 hours which is 76% of the designed MRT(22.3hr). Among the 6 compartments, the first compartment doesn't show the characteristic of perfect mixer, whereas, the other 5 compartments are working as perfect mixers. The output response of the first compartment is fit well with the simulated output of a model which consists of a perfect mixer with an exchange volume. It indicates that a quarter of the tank volume is working as a dead volume or an exchange volume. From the measured residence time distributions in each compartment, the appropriate sampling times after the change of operational condition of the electron beam accelerator were evaluated.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.1
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• pp.42-51
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• 2012

Objectives: To compare the exposure level of extremely low frequency (ELF) magnetic fields among semiconductor workers, shipyard welders and office workers. Methods: To measure the ELF magnetic field concentration, EMDEX LITE (Enertech, USA) were used and monitored for eight hours continuously. Five companies handling the electric and magnetic field (EMF) source were investigated, which the exposure groups were classified into three groups: semiconductor workers, welders, and office workers. Welder group was chosen as a high exposed group and office group as a low exposed group. Results: The arithmetic mean (${\pm}SD$) and geometric mean (GSD) of personal exposure level of semiconductor workers were 0.73 (${\pm}1.33$) ${\mu}T$, 0.43 (2.88) ${\mu}T$, respectively. The ceiling value ranged between 0.18 and 123.2 ${\mu}T$. Welders were exposed high with the arithmetic mean value of 3.46 (${\pm}\;13.46$) ${\mu}T$ and geometric mean value of 0.45 (4.70) ${\mu}T$, respectively, and ceiling value range of 75.5~129.6 ${\mu}T$. The exposure levels of office workers were low compared to other exposed groups; the arithmetic mean 0.05 (${\pm}0.13$) ${\mu}T$, geometric mean 0.03 (2.38) ${\mu}T$ and ceiling value range 0.37~3.35 ${\mu}T$. This study revealed statistically significant differences of the mean ELF magnetic field exposure doses among three groups (p < 0.01). Conclusions: The average ELF magnetic field exposure doses of semiconductor workers were much higher than those of office workers in control group, but were lower than those of welders in high exposure group.

• Journal of the Korean Society of Food Culture
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• v.27 no.1
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• pp.66-74
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• 2012

It is well known that sunflower (SF) sprout has more beneficial effects than SF seed due to increased levels of phytochemical components such as vitamins, total phenolics, and isoflavones during germination. This study investigated the physicochemical properties and antioxidative activities of SF seed during both germination and cultivation. In a proximate analysis, the water content of SF groat was 9.17% and then increased to 15.32% on the 11th day after seeding. On a dry weight basis, crude fat content decreased while the contents of carbohydrates, crude protein, and crude ash increased. As cultivation proceeded, the contents of minerals were in decreasing order of K, Mg, Ca, Na, Zn, Fe, Mn, and Cu, in which SF sprout cultivated for 9 or 11 days contained the highest mineral contents. Though vitamin C was not detected on SF groat, the content of vitamin C continuously increased up to the 5th day of cultivation and then decreased gradually. Vitamin E content in SF groat was higher than that in SF sprout. It was also found that the vitamin E content in SF sprout was the highest on the 5th day of cultivation. Daidzin was not detected in SF groat, but its concentration reached a maximum on the 5th day of cultivation in SF sprouts. Furthermore, higher amounts of daidzein were observed on the 3rd, 5th, and 9th days of cultivation. The highest total isoflavone content was observed on either the 3rd or 5th day of cultivation. The highest content of total phenolics was observed on the 5th of cultivation. When DPPH radical and peroxyl radical scavenging activities of SF sprout were measured in order to measure antioxidant efficacy, it was found that 5 day-cultivated SF sprout had the highest scavenging activities. In conclusion, SF sprout cultivated for 9 or 11 days was found to be a good source of minerals. Furthermore, the fifth-day after seeding was the optimal time for the production of SF sprout with effective natural antioxidant activity and high amounts of functional components such as vitamins, total phenolics, and isoflavones.

• Food Science and Preservation
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• v.18 no.3
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• pp.414-422
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• 2011

The optimum condition for phenolics contents extraction from purple sweet potato was 12 hrs. in 50% ethanol. The electron donating scavenging activities (DPPH), ABTS radical cation decolorization (ABTS) and antioxidant protection factor (PF) of Jami, Yeonjami and Shinjami were higher than general sweet potato, and thiobarbituric acid reaction substance (TBARs) was below 30%. The minimum inhibitory concentration (MIC) against Staphylococcus aureus and Escherichia coli on skin were each 5,000 and 2,500 ppm in all purple sweet potatoes, and MIC of Jami was the lowest as 2,500 ppm against Staphlococcus epidermidis. The whitening (tyrosinase inhibitory) activity of purple sweet potatoes was the highest as 62.5% and 48.7% in Jami water and ethanol extracts. The anti-inflammation (hyaluronidase inhibitory) activity of purple sweet potatoes was the highest as 25.3% and 94.4% in Jami water and ethanol extracts. The safety of cosmetic with Jam; extracts was assessed by various safety profiles. pH and viscosity change of essence for 90 days was not detected. Cosmetic was stable to temperature and light for 90 days. The result to measure changes of skin color and pore size of the skin was that an aged skin was more effective than young skin.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.183-190
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• 1995

Various factors such as sampling height in the chamber, sampling interval, sampling time at daytime and the effects of pedoturbation on methane emission during chamber installation were evaluated using a simplified closed static chamber method to measure methane flux in paddy soils. Sampling height of the chamber for representative samples was 65cm. An additional DC fan was required to attain an even methane gradient in the chamber. Considering the change of methane concentration and air temperature in the chamber, sampling is recommended to finish within 30 minutes after starting sampling. The aim of setting DC fan in the chamber was to get the thermal equilibrium in the chamber as well as the representative samples. Suitable time to collect the gas samples representing the day's methane flux was 0900~1200 hours. Gas sampling was possible even after installation of small chambers if the elapsed time was more than 6 hours and supporting stand would be to be added to minimize pedoturbation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.452-456
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• 2011

Glomalin has important roles in soil aggregation in agricultural lands including controlled horticultural lands. The objective of this study was to measure total glomalin content of soils treated conventional farming system (CFS), conventional farming system without pesticides (CFSWP), and organic farming system (OFS) for strawberry cultivation under greenhouse in Goseong-gun, Korea. The average concentration of total glomalin in the soils was significantly higher in the OFS ($2.00mg\;g^{-1}$) compared to the CFS ($1.68mg\;g^{-1}$). In addition, soil microbial biomass C content was 4.9 times higher in the OFS ($821mg\;kg^{-1}$) compared to the CFS ($169mg\;kg^{-1}$). Nitrogen uptake rate of strawberry was higher in the OFS (52.4%) than that in the CFS (13.0%). Furthermore, yield of strawberry in OFS ($51Mg\;ha^{-1}$) was significantly higher compared to CFS ($35Mg\;ha^{-1}$).

• Journal of Acupuncture Research
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• v.36 no.4
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• pp.245-250
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• 2019

Background: This study was designed to evaluate the clinical safety of Bee Venom (BV) pharmacopuncture at craniofacial acupuncture points. Methods: This was a retrospective study of 108 patients diagnosed with peripheral facial paralysis, trigeminal neuralgia, or facial spasm who were admitted to Kyung Hee University Korean Medicine Hospital at Gangdong, from April 1st, 2017 to August 30th, 2017. Patients were allocated into either, Group 1 (the non-allergy group of patients who did not have an allergic reaction to BV) or Group 2, the group who had allergic reactions to BV. To evaluate the clinical safety of BV pharmacopuncture after each treatment, several criteria were used to measure any side effects: outcome, Common Terminology Criteria for Adverse Events scale, Mueller HL scale, treatment decision after adverse reaction, causality, measures performed for patients with adverse reactions, and efficacy assessment. Results: BV pharmacopuncture delivered in 0.1-0.2 mL at a concentration of 1:30,000 at the craniofacial acupuncture points, showed no statistically significant differences in baseline characteristics between non-allergy Group 1 and allergy Group 2. Amongst the 108 patients, 11 reported side effects after BV pharmacopuncture treatment. These adverse events included rash (n = 7), pruritus (n = 5), swelling (n = 1), vesicles (n = 1), erythema (n = 1), and hives (n = 1). All side effects resolved without sequelae. Conclusion: In this study, BV pharmacopuncture delivered at low doses at the craniofacial acupuncture points, resulted in 10% of patients experiencing non serious side effects suggesting that BV pharmacopuncture was clinically well tolerated.