• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1280-1286
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• 2006

Three different virgin activated carbons made of each coal(Calgon), coconut(Samchully) and wood(Picabiol) based activated carbon(AC) were tested for an adsorption performance of 1,4-dioxane in a continuous adsorption column. Breakthrough behavior was Investigated that the breakthrough points of coal, coconut and wood based AC were observed as 3600 bed volumn(BV), 1440 BV and 144 BV respectively. Adsorption capacity(X/M) of coal, coconut and wood based AC was observed. The reported results of adsorption capacity showed that coal based AC was highest(578.9 ${\mu}g/g$), coconut based AC was intermediate(142.3 ${\mu}g/g$) and wood based AC was lowest(7.4 ${\mu}g/g$) due to increasing specific surface area. Moreover, carbon usage rates(CURs) for coal, coconut and wood based AC had been shown as 0.48 g/day, 1.41 g/day and 6.9 g/day respectively. The constant characteristic of the system, k of coal based AC was found to be 91.5 and k of coconut based AC was found to be 17.9. Removal efficiencies of 1,4-dioxane with different ozonation dosages(2 and 5 mg/L) for 20 min ozonation had been shown 38% and 87% respectively. There was no observation for biological removal of 1.4-dioxane by attached micro-organisms when used(3.1 years and over 5 years) biological activated carbon(BAC) without pretreatment of oxidation were employed. When a combination of ozonation(2 mg/L and 5 mg/L) and BAC process for $10{\sim}30$ min was applied, removal efficiency for 1,4-dioxine increased only $2{\sim}6%$ compared to only applying ozonation. Therefore removal efficiency of BAC process prior to using oxidation was proven to negligible. Consequently, the results presented in this paper provide a better insight into the adsorption performance of 1,4-dioxane. This observation suggests that using virgin activated carbon made of coal is the best selection for removal of 1,4-dioxane in the water treatment for an advanced treatment. It is clear from this research that longer EBCT for ozonation or higher ozone concentration are more effective operation methods for removal of 1,4-dioxane than longer EBCT in the BAC process.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.271-276
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• 1993

This study was carried out to prepare anchovy based powder for instant soup packed in tea bag which can be used handily as a extractives, and to determine the taste compounds of extractives of anchovy based powder for instant soup. The anchovy based powder for instant soup was made by adding of 72% in the redried anchovy, 14% in the sea tangle, 7% in the mushroom and 7% in the katsuobushi to the total mixtures. And the anchovy based powder for instant soup was packed in tea bag. The desirable extraction time are 5 min in package in tea bag with air permeability $100\;m^3/m^2/min$ and over 20 min in package in tea bag with air permeability $65\;m^3/m^2/min$, respectively. Judging from the result of extraction rate of total nitrogen, color and sensory evaluation in extractives of anchovy based powder for instant soup extracted by optimal extraction time, the quality in extractives of instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$ was superior to those of instant soup unpacked in tea bag and of instant soup packed in tea bag of air permeability $65\;m^3/m^2/min$. The principal taste compounds of extractives of anchovy based powder for instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$ were IMP (9.26 mg/100ml in 5% solution) and free amino acids (24.30 mg/100 ml in 5% solution) such as histidine, proline, lysine and taurine. Total creatinine, betaine and TMAO were seemed to act an auxiliary role in taste of extracives of anchovy based powder for instant soup packed in tea bag with air permeability $100\;m^3/m^2/min$.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.82-87
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• 2008

Algae are vital in the primary production of the aquatic ecosystem, having been considered as good indicators of the bioactivity of pesticides. Algae have short life cycle, respond quickly to environmental change and their diversity and density can indicate the quality of their habitat. The purpose of the study was to determine the growth inhibition effects of butachlor (Tech. 93.4%) and $K_2Cr_2O_7$ (Tech. 99.5%) in Selenastrum capriconutum, Scenedesmus subspicatus, Chlorella vulgaris and Nitzschia palea during and exposure period of 72 hours. The toxicological responses of S. capriconutum, S. subspicatus, C. vulgaris and N. Palea to butachlor, expressed in individual $ErC_{50}$ values were 0.0022, 0.019, 8.67 and $4.94\;mg\;L^{-1}$, respectively. NOEC values were 0.0008, 0.0016, 5.34 and $2.92\;mg\;L^{-1}$, respectively. S. capriconutum was more sensitive than the other algae species. The toxicological responses of S. capriconutum, S. subspicatus, C. vulgaris and N. palea to $K_2Cr_2O_7$ expressed as $ErC_{50}$ values were 0.91, 0.78, 0.85 and $0.57\;mg\;L^{-1}$, respectively. NOEC values were 0.2, 0.2, 0.2 and $0.18\;mg\;L^{-1}$, respectively. Growth inhibition of S. capriconutum, S. subspicatus, C. vulgaris and N. palea from PEC of butachlor were 100, 75, 0 and 0%, respectively.

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.197-205
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• 2016

Our country, which relies on maritime transport a majority of import and export trade volume and faced with unexpected accidents, it is difficult to operate the normal function of container terminal. It also caused by reliability issue raised is likely to be given a blow to the new volumes to attract and maintain existing volumes. Under this views, the container terminal is a situation that highlights the role of the harbor workers and cope with aggressive work to provide the best quality services to customers 365 days. On these grounds, the heavy work burden is passed on to the harbor workers and caused accidents every year. The study was analyzed the safety status of the container terminal under the real following the conditions as disaster status analysis, insufficient safety training circumstances and safety training from 2012 year to 2015 in the target current K.Y terminal. As a result of equipments safety training analysis, it shows that 2012 year happened 45 cases and 31 cases in 2013 year until not practicing the training over the Gantry Crane equipment. One hand 23 cases took place in 2014 while preparation training and the other intensive training period of 2015, 8 cases occurred. it shows that 2012 year happened 13 cases and 19 cases in 2013 year until not practicing the training over the Transfer Crane equipment. One hand 12 cases took place in 2014 while preparation training and the other intensive training period of 2015, 8 cases occurred. it shows that 2012 year happened 9 cases and 9 cases in 2013 year until not practicing the training over the Yard Tractor equipment. One hand 9 cases took place in 2014 while preparation training and the other intensive training period of 2015, 4 cases occurred. Because safety training of the container terminal was given to greatly impact on the mandatory safety training, self-educational enforcement and specified equipments safety training, hence the container terminal is to strengthen the safety education to prevent accidents in advance.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.533-541
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• 2017

Agricultural landscape has many ecosystem service functions. However, the development of the horticulture complex has no consideration for environmental conservation. Therefore, we analyzed the priorities of ecosystem service functions required for the composition. The study was conducted in three stages. As a result of the first survey, 17 functions were selected to be improved. In the second survey, 12 functions were selected excluding 5 functions. Finally, 1. Measures for water purification, 2. Groundwater recharge plan, 3. Surface water storage space, 4. Flood control measures, 5. Vegetation diversity space, 6. Carbon emission reduction plan, 7. Aquatic insect habitat space, 8. Amphibian reptiles 9. Landscape and Waste Management, 10. Bird Species Space, 11. Heat Island Mitigation Plan, 12. Experience / Ecological Education Plan. We proposed the structure, capacity, flow rate, arrangement and form of the water treatment facility to improve water quality by improving the function. We proposed a reservoir space of 7-10% for groundwater recharge. The development of reservoir and storage facilities suitable for the Korean situation is suggested for the surface water storage and flood control measures. And proposed to secure a green space for the climate cycle. Proposed habitat and nutrient discharge management for biodiversity. We propose green area development and wetland development to improve the landscape, and put into the facilities for experiential education. The results of the research can be utilized for the development and improvement of the horticultural complex.

• Radiation Oncology Journal
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• v.21 no.4
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• pp.291-298
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• 2003

Purpose: We report upon a web-based system for Patterns of Care Study (PCS) devised for Korean radiation oncology. This PCS was designed to establish standard tools for clinical quality assurance, to determine basic parameters for radiation oncology processes, to offer a solid system for cooperative clinical studies and a useful standard database for comparisons with other national databases. Materials and Methods: The system consisted of a main server with two back-ups in other locations. The program uses a Linux operating system and a MySQL database. Cancers with high frequencies in radiotherapy departments in Korea from 1998 to 1999 were chosen to have a developmental priority. Results: The web-based clinical PCS .system for radiotherapy in www.pcs.re.kr was developed in early 2003 for cancers of the breast, rectum, esophagus, larynx and lung, and for brain metastasis. The total number of PCS study items exceeded one thousand. Our PCS system features user-friendliness, double entry checking, data security, encryption, hard disc mirroring, double back-up, and statistical analysis. Alphanumeric data can be input as well as image data. In addition, programs were constructed for IRB submission, random sampling of data, and departmental structure. Conclusion: For the first time in the field of PCS, we have developed a web-based system and associated working programs. With this system, we can gather sample data in a short period and thus save, cost, effort and time. Data audits should be peformed to validate input data. We propose that this system should be considered as a standard method for PCS or similar types of data collection systems.

• Food Science and Preservation
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• v.22 no.4
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• pp.498-504
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• 2015

The purpose of the present study is to provide preliminary data for turning sweetpotato leaves into dehydrated vegetables. To achieve this goal, we have gone through the process of hot-air drying the leaves of sweetpotato that are usually thrown away and examined the drying speed and rehydration resilience, then made a comparative analysis of the general ingredients, lutein, $\beta$-carotene and chromaticity. The drying speed reached the peak at a temperature of $70^{\circ}C$. As for other general ingredients, there was no significant difference according to temperature. The content of lutein, which is a functional ingredient, was large in Shinmi with $171.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $73.75{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of $\beta$-carotene was large in Shinmi with $379.59{\mu}g/g$ at a temperature of $40^{\circ}C$; small in Hayanmi with $170.78{\mu}g/g$ at a temperature of $70^{\circ}C$. The content of functional materials was the largest at a temperature of $40^{\circ}C$, and decreased in the order of temperatures at $50^{\circ}C$, $60^{\circ}C$, and $70^{\circ}C$. As for rehydration stability, rehydration rate in both Shinmi and Hayanmi was the highest at a temperature of $40^{\circ}C$ with 233.93% and 223.47% respectively. To summarize, the quality of dried sweet potato leaf was more affected by temperature than by drying time, and low temperature drying resulted in better product value.

• Food Science and Preservation
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• v.17 no.1
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• pp.1-8
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• 2010

We investigated the effect of freezing on changes in the chemical components of semi-dried red pepper (SDRP). We used storage temperatures of $0^{\circ}C,\;-10^{\circ}C,\;-20^{\circ}C,\;and\;-70^{\circ}C$. After 30 days of storage, capsaicin content had decreased by 40% at $0^{\circ}C$ and by 21% at $-20^{\circ}C$. Initial vitamin C content was 1,358.02 mg%. Compared with control, the $0^{\circ}C$ storage group showed a significant decrease in vitamin C content but no such decrease was noted in the $-20^{\circ}C$ and $-70^{\circ}C$ storage groups after 30 days. ASTA values were not influenced by storage temperature or period, in agreement with previous results. We concluded that storage was effective at temperatures of less than $-20^{\circ}C$. Next, both dried red pepper (DRP) and SDRP were stored at $-20^{\circ}C$ for 12 months. DRP had the lower level of capsaicinoids (55.01 mg%) owing to the long drying time. After 12 months, SDRP capsaicinoid had decreased by 30-33%, compared with a decrease of 54% in DRP. Initial vitamin C contents were 721.48 and 955.25 mg% in DRP and SDRP, respectively, and, after 12 months, vitamin C loss in the SDRP group (37%) was less than that in fresh red pepper (FRP) samples (45%). Initial $\beta$-carotene content was greatest in the FRP group (259.82 mg%), and that of DRP decreased by 20% after 12 months. The color a/b value of SDRP (1.40) was greater than that of DRP (1.00).

• Journal of the Korean Magnetics Society
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• v.17 no.2
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• pp.81-85
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• 2007

MnTe layers of high crystalline quality were successfully grown on Si(100) : B and Si(111) substrates by molecular beam epitaxy (MBE). Under tellurium-rich condition and the substrate temperature around $400^{\circ}C$, a layer thickness of $700{\AA}$ could be easily obtained with the growth rate of $1.1 {\AA}/s$. We investigated the structural, magnetic and transport properties of MnTe layers by using x-ray diffraction (XRD), superconducting quantum interference device (SQUID) magnetometry, and physical properties measurement system (PPMS). Characterization of MnTe layers on Si(100) : B and Si(111) substrates by XRD revealed a hexagonal structure of polycrystals with lattice parameters, ${\alpha}=4.143{\pm}0.001{\AA}\;and\;c=6.707{\pm}0.001{\AA}$. Investigation of magnetic and transport properties of MnTe films showed anomalies unlike antiferromagnetic powder MnTe. The temperature dependence of the magnetization data taken in zero-field-tooling (ZFC) and field-cooling (FC) conditions indicates three magnetic transitions at around 21, 49, and 210 K as well as the great irreversibility between ZFC and FC magnetization in the films. These anomalies are attributable to a magnetic-elastic coupling in the films. Magnetization measurements indicate ferromagnetic behaviour with hysteresis loops at 5 and 300 K for MnTe polycrystalline film. The coercivity ($H_c$) values at 5 and 300 K are 55 and 44 Oe, respectively. In electro-transport measurements, the temperature dependence of resistivity revealed a noticeable semiconducting behaviours and showed conduction via Mott variable range hopping at low temperatures.

• Journal of The Korean Association For Science Education
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• v.37 no.2
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• pp.347-358
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• 2017

The purpose of this study is to research on the professional development of pre-service chemistry teachers in terms of personal practical knowledge(PPK), and draw a discussion for pre-chemistry teacher education. A reflective discussion through a Community of Practice(CoP) activity has been conducted with 5 pre-service chemistry teachers studying in a college of education located in Seoul. The analysis of the results reveals that 'Subject-matter knowledge' is leaning toward massive chemical contents, 'Curriculum knowledge' is below the level of selecting, analyzing, and applying curriculum materials. 'Instruction knowledge', especially the knowledge of chemistry experiment and research, is not enough to lead secondary students' scientific experiment. 'Milieu of school knowledge' is stunted in growth for the reason of communication-deficiency between a college of education and a community, and among education- related groups. 'Self-knowledge' has been diminished not only because there is a bad influence from college classmates not wanting to be a teacher, but also a lack of communication in the chemistry-education department which can make pre-teachers' belief strong. In conclusion, it is especially needed for the chemistry-education department to strengthen pre-teachers' 'Self-knowledge' in order to develop PPK. This study suggests operating 'a professional community' that has a periodic meeting with pre-service teachers, teachers, professors, community people, education practitioners, and researchers. In addition, it would be effective for increasing pre-teachers' PPK to reconsider depth and direction of 'Subject-matter knowledge', to give an opportunity to examine curriculum materials critically and reorganize them, to improve the course of chemistry experimental subject to the way of improving pre-teachers' leadership in chemistry inquiry experiment, and to raise the quality of educational service activities.