• Clinical and Experimental Reproductive Medicine
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• v.37 no.2
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• pp.135-142
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• 2010

Objective: To evaluate the effectiveness of soft stimulation protocol using GnRH antagonist/clomiphene citrate (CC)/recombinant FSH (rFSH) in patients undergoing controlled ovarian stimulation (COS) with intrauterine insemination (IUI), compared with GnRH antagonist multiple dose protocol (MDP) using GnRH antagonist/rFSH. Methods: Eighty infertile women were randomized to soft stimulation protocol group (n=40) or GnRH antagonist MDP group (n=40). In both groups, IUI was performed 36~40 hours after hCG injection. Statistical analysis was performed using Student's t-test, $\chi^2$ test or Fisher's exact test as appropriate. Results: Total dose and days of rFSH required for COS were significantly fewer in soft stimulation protocol group (p<0.001, p<0.001). A premature LH surge did not occur in any patients of both groups. Clinical pregnancy rate per cycle was similar between the two groups. Conclusion: Soft stimulation protocol provides comparable pregnancy rates to GnRH antagonist MDP despite fewer total dose and days of rFSH, and so can become one of the patient-friendly, cost-effective alternatives for infertile patients undergoing COS with IUI.

• Journal of the Korean earth science society
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• v.28 no.1
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• pp.64-74
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• 2007

The marine seismic prospecting using a research vessel in the shallow sea near the coastal area has certain limits according to the water depth and survey environment. Also, for the electrical resistivity survey at seashore area, one may need a specially designed high-voltage source to penetrate the very conductive surface layer. Therefore, we have conducted a feasibility study on the application of magnetotelluric method (MT), a passive geophysical method, on investigating of shallow marine environment geology. Our study involves both theoretical modeling and field survey at the tidal flat area which represent the very shallow marine environment. We have applied the audio-frequency magnetotelluric (AMT) method to the intertidal deposits of Gunhung Bay, west coast of Korea, and analysed the field data both qualitatively and quantitatively to investigate the morphology and sedimentary stratigraphy of the tidal flat. The inversion of AMT data well reveals the upper sedimentary layer of Holocene intertidal sediments having a range of 13-20 m thickness and the erosional patterns at the unconformable contact boundary. However, the AMT inversion results tend to overestimate the depth of basement (30-50 m) when compared with the seismic section (27-33 m). Since MT responses are not significantly sensitive to the resistivity of middle layer or the depth of basement, the AMT inversion result for basement may have to be adjusted using the comparison with other geophysical information like seismic section or logging data if possible. But, the AMT method can be an effective alternative choice for investigating the seashore area to get important basic informations such as the depositional environment of the tidal flat, sea-water intrusion and the basement structure near the sea shore.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.258-265
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• 2009

To develop environmentally friendly constructed wetlands(CWs) for treating domestic sewage which was produced in farming and fishing village, the efficiency of water treatment at different ventilation systems in the vertical bed, depths of horizontal bed, and sewage loads was investigated. In the vertical bed, BOD and COD by duplex ventilation system were lower than those by single ventilation system. But T-N and T-P concentrations by both ventilation systems in the vertical bed were little different. In the horizontal bed, BOD, COD, T-N and T-P in 1.0 m and 1.3 m depths were little different. To reduce the CWs' area and to improve the pollutant removal efficiencies, the optimum depth of horizontal bed was 1.3 m. In single and duplex ventilation CWs, the removal rate of BOD, COD, SS, T-N and T-P decreased slightly with the sewage load increases. In same sewage load conditions, the removal rates of BOD, COD, SS, T-N and T-P by duplex ventilation CWs were higher than those by single ventilation CWs. In summary, to effectively treat domestic sewage from farming and fishing village, the optimum constructed wetlands would be the duplex ventilation CWs.

• Korean Journal of Weed Science
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• v.30 no.3
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• pp.233-242
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• 2010

This study was conducted to know that if ionic liquids can be applicable as control agents of harmful algae in water-ecosystem and to find out problems caused by ionic liquid application. Firstly, the differential selectivity of various fresh-water algal species to several 1-alkyl-3-methylimidazolium chloride ionic liquids was investigated. There was a distinct differential response between alkyl chain lengths from butyl to dodecyl and towards the algal organisms : Generally algicidal activity was increased with increase of chain length and among the algae used in this study, Stephanodiscus hantzschii f. tenuis, Oscillatoria tenuis and Spirulina pratensis were most sensitive to 1-dodecyl-3-methylimidazolium chloride (MAIC12), next was Microcystis aeruginosa, and the others were relatively less sensitive to the chemical. The selectivity degree was about ten to twenty times based on the $EC_{80}$ (Effective concentration required for 80% growth inhibition). Secondly, an activity persistence of ionic liquids was investigated in natural mimic condition (using water bottle containing soil-sediments under the greenhouse condition). At the application of $1.0{\mu}g\;mL^{-1}$ of 1-octyl-3-methylimidazolium chloride (MAIC8), the algal growth did not occur at all until 6 days after treatment(DAT) and observed a only little growth at 9 DAT. But the algae grew rapidly after 9 DAT. So at 20 DAT, total chlorophylls was $264.4{\mu}g\;L^{-1}$ and the growth was inhibited by 58.2% compared to untreatment. On the other hand, MAIC12 also had a similar persistence pattern to MAIC8, showing nearly 5 times more activity than MAIC8. At 20 days after $0.2{\mu}g\;mL^{-1}$ application of MAIC12, that is, total chlorophylls was $251.2{\mu}g\;L^{-1}$ and the growth was inhibited by 55.2% compared to untreatment. In summary, 1-alkyl-3-methylimidazolium chloride ionic liquids is likely to be applicable for selective control of harmful algae as potent compounds having long lasting activity. However, the difficulty of degradation seems to be a limiting factor in an eco-friendly application of the compounds.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.69-75
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• 2006

Improper disposal of petroleum and spills from underground storage tanks have created large areas with highly toxic contamination of the soil and groundwater. Methyl tert-butyl ether (MTBE) is widely used as a fuel additive because of its advantageous properties of increasing the octane value and reducing carbon monoxide and hydrocarbon exhausts. However, MTBE is categorized as a possible human carcinogen. This research investigated the Modified Photo-Fenton system which is based on the Modified Fenton reaction and UV light irradiation. The Modified Fenton reaction is effective for MTBE degradation near a neutral pH, using the ferric ion complex composed of a ferric ion and environmentally friendly organic chelating agents. This research was intended to treat high concentrations of MTBE; thus, 1,000 mg/L MTBE was chosen. The objectives of this research are to find the optimal reaction conditions and to elucidate the kinetic and mechanism of MTBE degradation by the Modified Photo-Fenton reaction. Based on the results of experiments, citrate was chosen among eight chelating agents as the candidate for the Modified Photo-Fenton reaction because it has a relatively higher final pH and MTBE removal efficiency than the others, and it has a relatively low toxicity and is rapidly biodegradable. MTBE degradation was found to follow pseudo-first-order kinetics. Under the optimum conditions, [$Fe^{3+}$] : [Citrate] = 1 mM: 4 mM, 3% $H_2O_2$, 17.4 kWh/L UV dose, and initial pH 6.0, the 1000 ppm MTBE was degraded by 86.75% within 6 hours and 99.99% within 16 hours. The final pH value was 6.02. The degradation mechanism of MTBE by the Modified Photo-Fenton Reaction included two diverse pathways and tert-butyl formate (TBF) was identified to be the major degradation intermediate. Attributed to the high solubility, stability, and reactivity of the ferric-citrate complexes in the near neutral condition, this Modified Photo-Fenton reaction is a promising treatment process for high concentrations of MTBE under or near a neutral pH.

• Culinary science and hospitality research
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• v.21 no.4
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• pp.101-120
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• 2015

This study was conducted to examine the relation between a mother's LOHAS lifestyle propensity, healthy dietary life, and nutrient intake perceived by Chinese university students. The subjects consisted of 376 Chinese university students. The research results are summarized below. The mother's LOHAS attitude index was 76.02 points out of a perfect score of 100 points. High LOHAS attitude factors of mothers were 'health', whereas 'social welfare' scored low. The highest LOHAS attitude items of mothers that Chinese university students perceived was 'My mother uses health food, organic food, clean food'(4.26 points). Males who lived on their own in a large city and have normal BMI ($18.5{\sim}22.9kg/m^2$) perceived a high mother's LOHAS score. The highest food habit variables are 'eating without spilling food' 'cleaning up after meals around' and 'washing my hands before meals'. The highest healthy dietary life item is 'I try to maintain a pleasant and enjoyable life'(3.83 points). The highest nutrient intake attitude score is 'I tend to eat yellowish-green vegetables every day.'(3.92 points). According to mother's LOHAS lifestyle score, it was verified that the higher mother's LOHAS lifestyle score, the higher children's food habit, healthy dietary life, and nutrient intake score are. Mother's environment-friendly LOHAS attitude index has a meaningful impact on the child's food habits, healthy dietary life, and nutrient intake.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.215-224
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• 2017

Arsenic (As) is known to be the most toxic element and frequently detected in groundwater environment. Inorganic As exists as arsenite [As(III)] and arsenate [As(V)] in reduced and oxidized environments, respectively. It has been reported that the toxicity of arsenite is much higher than that of arsenate and furthermore arsenite shows relatively higher mobility in aqueous environments. For this reason, there have been numerous researches on the process for oxidation of arsenite to arsenate to reduce the toxicity of arsenic. In particular, photooxidation has been considered to be simple, economical, and efficient to attain such goal. This study was conducted to evaluate the applicability of naturally-occurring goethite as a photocatalyst to substitute for $TiO_2$ which has been mostly used in the photooxidation processes so far. In addition, the effects of several factors on the overall performance of arsenite photocatalytic oxidation process were evaluated. The results show that the efficiency of the process was affected by total concentration of dissolved cations rather than by the kind of those cations and also the relatively higher pH conditions seemed to be more favorable to the process. In the case of coexistence of arsenite and arsenate, the removal tendency by adsorption onto goethite appeared to be different between arsenite and arsenate due to their different affinities with goethite, but any effect on the photocatalytic oxidation of arsenite was not observed. In terms of effect of humic acid on the process, it is likely that the higher concentration of humic acid reduced the overall performance of the arsenite photocatalytic oxidation as a result of competing interaction of activated oxygen species, such as hydroxyl and superoxide radicals, with arsenite and humic acid. In addition, it is revealed that the injection of oxygen gas improved the process because oxygen contributes to arsenite oxidation as an electron acceptor. Based on the results of the study, consequently, the photocatalytic oxidation of aqueous arsenite using goethite seems to be greatly feasible with the optimization of process.

• Economic and Environmental Geology
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• v.54 no.2
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• pp.299-308
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• 2021

Fe(II) released from mining activities is precipitated as various Fe(III)-oxyhydroxides when exposed to an oxidizing environment including mine drainage. Ferrihydrite, one of the representative precipitated Fe(III) minerals, is easy to adsorb heavy metals and other pollutants due to the large specific surface area caused by very low crystallinity. Ferrihydrite is transformed to thermodynamically more stable goethite in the natural environment. Hence, information on the transformation of ferrihydrite to goethite and the related mobility of heavy metals in the acid mine drainage is important to predict the behaviors of those elements during ferrihydrite to goethite transition. The behaviors of heavy metals during the transformation of ferrihydrite to goethite were investigated for core samples collected from an AMD treatment system in the Heungjin-Taemaek coal mine by using X-ray diffraction (XRD), chemical analysis, and statistical analysis. XRD results showed that ferrihydrite gradually transformed to goethite from the top to the bottom of the core samples. Chemical analysis showed that the relative concentration of As was significantly high in the core samples compared with that in the drainage, indicating that As was likely to be adsorbed strongly on or coprecipitated with iron oxyhydroxide. Correlation analysis also indicated that As can be easily removed from mine drainage during iron mineral precipitation due to its high affinity to Fe. The concentration ratio of As, Cd, Co, Ni, and Zn to Fe generally decreased with depth in the core samples, suggesting that mineral transformation can increase those concentrations in the drainage. In contrast, the concentration ratio of Cr to Fe increased with depth, which can be explained by the chemical bond of iron oxide and chromate, and surface charge of ferrihydrite and goethite.

• Journal of the Korea Society of Computer and Information
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• v.26 no.4
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• pp.203-211
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• 2021

With the advent of the age of"untact" modern people are pursuing a healthy body and mind. In order to achieve well-being, LOHAS and Wellness,people prefer to use natural affinity alternative therapies, Aromatherapy. This study focuses on women in their 20s~50s in Zhejiang Province, with the aim of investigating their knowledge and use of essential oils.The questionnaire was divided into four parts: 3 questions for general question, 11 questions for knowledge, 13 questions for use and 9 questions for satisfaction. In addition, the study was conducted using the WeChat and the Wenjuanxing Program from July 5 to August 30, 2019. Finally, a total of 617 questionnaires were analyzed. In this study, SPSS WIN 21.0 program is used for frequency analysis. The level of knowledge and satisfaction is verified by Cronbach's α. And the following analysis results were obtained by frequency analysis, descriptive statistics, Chi-squared test(χ2), one-way ANOVA on the understanding level and usege of essential oils according to age. The results were as follows. The most common characteristics of subjects were the 20s, university students, essential oil recognition was high in having experience. There is no great difference in knowledge or satisfaction depending on age. knowledge and satisfaction was moderate. The results of experience in the use of essential oils were higher among all age groups, those who in their 30s did not think that the use of essential oils would be effective. However, people in their 20s and 40s and older have unclear answers, indicating that results showed a difference. The results of the survey on usage showed that there were significant differences in period of use, place of purchase, method of purchase, purpose of use, place of use, number of use, frequency of use, body parts of use. According to the study, awareness and knowledge of essential oils vary according to age, and those in their 20s use essential oils for facial skin, and those in their 30s and older use essential oils for stress relief and body management. This study provides basic information on marketing related to diversified essential oil products according to age.

• Journal of the Daesoon Academy of Sciences
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• v.38
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• pp.209-242
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• 2021

This manuscript started with the purpose of producing research that investigated and verified how Buddhism was understood by Seongdam (性潭) Song Hwan-gi (宋煥箕), the founder (宗匠) of Horon (湖論) who was active around the early 19 th century. Song Hwan-gi, Uam (尤菴) Song Si-yeol (宋時烈)'s fifth generation, was a scholar who had a deep sense of duty to inherit the Theory of Uam (尤菴學), and he adhered to the Confucian theory of genealogy (道統論) and Anti-Heresy Discourses. Thus, this manuscript expressed curiosity about Song Hwan-gi's understanding of Buddhism, which was the representative heresy. This manuscript examined the naming method of Buddhist clergy (僧侶), degree of pedagogical knowledge, and critical statements that were made concerning Buddhist tales (說話). Meanwhile, it is noticeable that the terms of address for Buddhist clergy were composed of four categories: general terms, honorific forms, palanquins [輿], and miscellaneous terms of address. This scheme conforms to the Buddhist-friendly aspects of Song Hwan-gi. Examples of these terms of address include Danseung (擔僧) and Yeoseung (輿僧), both of which were Buddhist clergy who carried palanquins. Naturally, Song Hwan-gi was helped by Buddhist clergy when he went sightseeing on famous mountains. In the meantime, Song Hwan-gi's pedagogical knowledge can be shown to be not especially profound based on his understanding of The Diamond Sutra, The Avatamska Sutra, and The Shurangama Sutra. Cheongnyansan Travel Records (淸凉山遊覽錄) and Dongyu Diary (東遊日記) make it clear that Song Hwan-gi had no interest in taking refuge in the three treasures of Buddhism (佛法僧 三寶). It is rather the case that he was deeply critical of Buddhism. On the other hand, Song Hwan-gi expressed profound sadness when he encountered the dilapidated remains (古蹟) of Buddhist temples and hermitages. Consequentially, it can be concluded that Song Hwan-gi's understanding of Buddhism contained examples of affirmation, acceptance, denial, and exclusion.