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A Review of Model and Modeling in Science Education: Focus on the Metamodeling Knowledge (과학교육에서 모델 및 모델링에 대한 고찰 -메타모델링 지식을 중심으로-)

  • Cho, Hye Sook;Nam, Jeonghee;Oh, Phil Seok
    • Journal of The Korean Association For Science Education
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    • v.37 no.2
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    • pp.239-252
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    • 2017
  • The purpose of this study is to examine metamodeling knowledge and its components, which means knowledge about model and modeling required for students and teachers for successful application of modeling in the field of science education based on research literature. For this, we analyzed and categorized major previous studies on modeling and modeling through research literature methods. Metamodeling knowledge aims to recognize models and modeling and is the most crucial element to create a scientific model in scientific modeling practice. The point of view of metamodeling knowledge proposed in this study is categorize nature of model, multiplicity of model, purpose of model, modeling process, and evaluation and revision of model. Students should be able to achieve more in-depth understanding through the awareness of the nature of the model. The development of metamodeling knowledge can facilitate students' science learning.

A Study on the Mill Scale Pretreatment and Magnetite Production for Phosphate Adsorption (인 흡착을 위한 Mill Scale 전처리 및 Magnetite 제조 연구)

  • Chun, Hyuncheol;Choi, Younggyun
    • Journal of Korean Society of Environmental Engineers
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    • v.37 no.4
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    • pp.246-252
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    • 2015
  • In steel factory, hot roller cleaning process produces a lot of iron oxide particles called as mill scale. Major components of these particles are wustite (FeO), magnetite ($Fe_3O_4$), and hematite ($Fe_2O_3$). In this study, we tried to produce pure magnetite from the mill scale because of the largest phosphate adsorption capacity of the magnetite. The mill scale was treated with acid (HCl+$H_2O_2$), base (NaOH), and acid-base ($H_2SO_4$+NaOH). Batch adsorption tests showed the acid and/or base treatment could increase the phosphate adsorption capacity of the iron oxides from 0.28 to over 3.11 mgP/g. Magnetite, which could be obtained by acid and base treatment of the mill scale, showed the best adsorption capacity. From the kinetic analysis, both Freundlich and Langmuir isotherm well described the phosphate adsorption behavior of the magnetite. In Langmuir model, maximum phosphate adsorption capacity was found to be 5.1 mgP/g at $20^{\circ}C$.

Simultaneous Analysis Method for Polar and Non-polar Ginsenosides in Cultivated Wild Ginseng by Reversed-phase HPLC-CAD (HPLC-CAD에 의한 산양삼의 극성 및 비극성 ginsenoside 동시 분석)

  • Ok, Seon;Kang, Jae Seon;Kim, Kang Min
    • Journal of Life Science
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    • v.26 no.2
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    • pp.247-252
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    • 2016
  • Cultivated wild ginseng is a widely used dietary supplement and medicinal herb. The aim of this study was to optimize the ginseng using high performance liquid chromatography (HPLC)- charged aerosol detection (CAD) for ginsenoside analysis. CAD measures the physical property of an analyte and responds to almost all non-volatile species, independent of their nature, spectral properties, or particle size. It has become widely employed in pharmaceutical analysis. The cultivated wild ginseng extracts were analyzed for compositions of ginsenosides Rb1, Rd, Rg1, Rf, Re, and Rh1. The optimal analysis condition was set up from an experiment using a gradient. Ten grams of cultivated wild ginseng were extracted with 95% EtOH 100 ml for 24 hr at 80℃. The contents of the 6six major ginsenosides in the cultivated wild ginseng extract were Rb1 (5.48±0.12 mg/g), Rd (5.33±0.14 mg/g), Rg1 (12.80± 0.05 mg/g), Rf (19.08±0.68 mg/g), Re (19.87±0.05 mg/g), and Rh1 (16.47±0.16 mg/g), respectively. HPLC showed that the protopanaxatriol group (Rg1, Rf, Re, Rh1) had more content than the protopanaxadiol group (Rb1, Rd) in cultivated wild ginseng extract. In summary, the ginsenosides were identified with HPLC-CAD analysis, and their presence and quantity imply the importance of quality control, as well as the pharmacological activity of the ginseng root.

Mineralogy and Geochemistry of Minerals from the Jinwon Gold-silver Deposit, Republic of Korea (진원 금-은 광상에서 산출되는 광물들의 산출상태 및 화학조성)

  • Yoo, Bong Chul
    • Economic and Environmental Geology
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    • v.49 no.6
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    • pp.491-504
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    • 2016
  • Jinwon Au-Ag deposit is located in the Uijin gun which is southeast 300 km from Seoul. The deposit area consists of mainly Precambrian Hongjesa granite, which occurs as porphyroblastic texture, medium grain and composed of quartz, feldspar and mica. This deposit consists of four parallel hydrothermal quartz veins that fill NE oriented fractures in Precambrian Hongjesa granite. The grade of quartz veins contain from 3.0 to 21.4 g/t (average 6.4 g/t) gold and from 5.0 to 252.0 g/t (average 117.9 g/t) silver, respectively. They vary from 0.2 m to 0.6 m (average 0.3 m) in thickness and extend to about 200 m in strike length. Quartz veins occur as massive, network, cavity, breccia, crustiform, comb and zonal textures. Wallrock alteration has silicification, sericitization, pyritization and argillitization. The mineralogy of the quartz veins consists of quartz, arsenopyrite, cassiterite, pyrite, sphalerite, chalcopyrite, galena, electrum, tetrahedrite, canfieldite, argentite, Ag-Sb-S mineral, Mn-Fe-O mineral, Pb-O mineral and Pb-P-Cl-O mineral(chloro-pyromorphite). Chemical compositions of minerals from this deposit are as followed; Fe/Fe+Mg of sericite is from 0.32 to 0.71, As content of arsenopyrite ranges from 27.91 to 30.33 atomic %, FeS content of sphalerite range from 9.77 to 16.76 mole %, Ag content of electrum is from 29.42 to 37.41 atomic % and Ag content of tetrahedrite range from 32.17 to 36.53 wt.%, respectively. Baased on mineralogy and chemical compositions of minerals from Jinwon Au-Ag deposit, deposition of minerals was caused by a change in temperature, oxygen fugacity($fO_2$) and sulfur fugacity($fS_2$) from the near neutral hydrothermal fluid evolved by reaction with wallrock.

Nursing Time Use in a Newborn Intensive Care Unit (NICU) (신생아중환자실 간호사의 간호업무량 분석)

  • Jun, Eun-Kyoung
    • Journal of Korean Academy of Nursing Administration
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    • v.6 no.1
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    • pp.55-81
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    • 2000
  • This study examined nursing care in a Newborn Intensive Care Unit (NICU) by reviewing nursing activities for the newborns. Through direct observation, time used for nursing care according to the nursing activity, shift, day of the week, and position of the nurses was measured. This study was done on November 15, 21, 24, 1999 at a university medical center hospital and included eight nurses and 179 newborns as the study subjects. The data were collected from the medical records, and by using a nursing activity record for the NICU, and a nursing activity time record for the NICU. The first step in the data collection process was to develop a list of nursing activities which was done through a literature review, examination of medical affairs and duty records. Content validity was measured by a panel of three professors who were experienced clinicians. In the second step two pre-training sessions were held with three sophomore student nurses who then measured the time for each nursing activity using a stopwatch. The data were analyzed using frequencies for nursing activities, averages, percentages and ANOVA for differences between shift and between days of the week, and percentages and t-test for differences according to position of the nurse. The results are as follows: 1) The total number of activities was 156, direct or indirect nursing activities. Direct nursing activity classified according to physical, educational, emotional/social/economic/spiritual needs. There were 109 direct nursing activities in 16 fields. 2) The order of nursing activities, according to time required, was record keeping, nutritional care, measurement/observation, medication, hygiene care, examination and specimen collection, and checking supplies, and according to frequency, measurement/ examination, record keeping, nutrition care, hygiene care, elimination care and medication. 3) According to shift, direct care during the night shift at 313.4 minutes was the longest time and indirect nursing care during the night shift at 252.2 minutes was the highest time. 4) For days of the week, Monday had the highest time for direct care 275.8 minutes (34.6%) and Wednessday had the highest time for indirect nursing care 269.6 minutes (36.1%). 5) For nursing time according to position of nurse, general nurses had the highest for direct care (330.7 minutes), nurse managers for indirect nursing activities (239.0 minutes) and general nurses for individual private time (63.9 minutes). The results of this study show that the major nursing time consuming activities included record keeping, nutrition care and measurement/examination. For newborns, time needs to be allowed for care to be sensitive, sophisticated and specialized rather than concentrated on indirect nursing tasks such as record keeping. Therefore, it is imperative to develop computerized systems that support a systematic approach to record keeping which is more efficient. Moreover, nursing needs according to shift, day or position of nurse can be utilized in assessing nursing resources through a computerized process.

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A Study on Risks and Returns Using A Housing Capital Asset Pricing Model (CAPM): the Case of Three Gangnam Districts Apartment Market in Seoul (주택 자본자산가격결정모형(Capital Asset Pricing Model)을 활용한 위험과 수익 분석: 서울 강남 3개구 아파트시장의 경우)

  • Lee, Jong-Ah;Jeong, Jun-Ho
    • Journal of the Economic Geographical Society of Korea
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    • v.13 no.2
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    • pp.234-252
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    • 2010
  • This paper examines the tendency of housing assets to become increasingly quasi-financial assets by analyzing the relationships between risks and returns in three Gangnam districts (Gangnam-gu, Seocho-gu and Songpa-gu) apartment markets in Seoul, especially for the apartments to be reconstructed, capitalizing upon some capital asset pricing models (CAPM). A single factor CAPM model shows positive relationships between risks and returns regardless of the types of apartments in three Gangnam districts. Multi-factors CAPM models also confirm that the market and SMB (small minus big) factors are positively related to the rate of returns regardless of the types of apartments. However, the unsystematic risk factor is found to be statistically positive especially for the apartments to be reconstructed, while the momentum factor is dependent upon the regression models used. An analysis on some portfolios classified by the size of apartments and price volatility and/or beta values suggests that there are the positive linear relationships between risks and returns and the SMB factor is clearly found to be significant in determining the rate of returns. In particular, housing assets are highly highlighted as investment goods and/or quasi financial assets for the apartments to be constructed in the Gangnam housing.

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A Satisfaction about Technical Specialized High School Supported by Seoul Metropolitan Office of Education (서울시교육청 지원형 공업계 특성화 고등학교의 만족도 분석)

  • Lee, Myung-Hun;Lee, Byung-Wook
    • 대한공업교육학회지
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    • v.37 no.1
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    • pp.1-19
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    • 2012
  • The purpose of this study was to analysis a satisfaction about technical specialized high school supported by Seoul metropolitan office of education. The study was carried out through questionnaire survey method. The population sample for the study constituted 894 completed questionnaires from sample of 1050 technical specialized high school students and parents. A survey questionnaire for students consisted of 20 scales, and it for parents consisted of 16 scales. Both descriptive and inferential statistics were employed for data analysis. Major findings of this study were as follows: First, satisfaction perceived technical specialized high school students supported by Seoul metropolitan office of education was high. In sub-variables of school satisfaction, 'school facilities' was the highest, and 'relation to teacher' was the lowest. Second, three related variables were found to be significant in affecting the satisfaction of technical specialized high school students supported by Seoul metropolitan office of education. They were grade of students, achievement of students, and school type(public school/private school). Third, their parents were satisfied with technical specialized high school supported by Seoul metropolitan office of education. Fourth, gender difference of parents and school type(public school/private school) had no appreciable affect on satisfaction of parents.

Enzymatic Synthesis of Diacylglycerol Oil from Glyceryl Mono-oleate and Conjugated Linoleic Acid Using a Stirred-Batch Type Reactor (회분식 반응기를 이용한 Glyceryl Monooleate와 Conjugated Linoleic Acid로부터 효소적 반응을 통한 디글리세롤 유지의 합성)

  • Jeon, Mi-Sun;Lee, Ki-Teak
    • Food Science and Preservation
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    • v.16 no.2
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    • pp.246-252
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    • 2009
  • Diacylglycerol(DAG) was produced by enzymatic esterification of glyceryl mono-oleate(GMO) and conjugated linoleic acid(CLA) in a stirred-batch type reactor. The reaction was catalyzed by lipozyme RMIM(an immobilized lipase from Rizomucor miehei). DAG was isolated by a short-path distillation process and decolorized. DAG oil was composed of 87.3% DAG, 11.4% triacylglycerol(TAG), and 1.5% monoacylglycerol(MAG)(all w/w). Major fatty acids in DAG oil were oleic acid(54%), CLA(31.1%), and linoleic acid(7%). DAG oil iodine,and acid values were 108.8, 2.57, and 1, respectively. The DAG oil solid fat index(SFI) and thermograms were obtained using differential scanning calorimetry.

Changes of Growth Characteristics, Rosmarinic Acid and Essential Oil Contents according to Harvest time in Agastache rugosa O. Kuntze (배초향의 수확시기별 생육특성 및 로즈마린산과 정유함량의 변화)

  • Lee, Sung-Woo;Kim, Jung-Bong;Kim, Kwan-Su;Kim, Myong-Suk
    • Korean Journal of Medicinal Crop Science
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    • v.7 no.2
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    • pp.83-88
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    • 1999
  • To find out proper harvest time and to select a variety having high yield and good quality, growth characteristics and contents of rosmarinic acid and essential oil were investigated according to harvest time of Agastache rugosa O. Kuntze collected in Korea. Only the number of flower cluster per plant among growth characteristics of 7 collections showed not significant difference. The range of dry matter weight of above-ground part used as crude drug was $666{\sim} 1328kg/10a$ and the weight of flower cluster and root was not significant among the plant parts of collections. Dry matter weight of top was the highest on Sep. 20, full-bloom stage. Rosmarinic acid contents among in 7 collections showed significant difference and the range were $0.32{\sim}2.34%$ in flower, $0.97{\sim}1.64%$ in leaf, $0.03{\sim}0.21%$ in stem and $0.91{\sim}6.56%$ in root. The contents of rosmarinic acid and essential oil in leaf was 3.76%, 5.78% before flowering and 1.55%, 4.28% after flowering respectively. The total content of rosmarinic acid of all plant parts was decreased after flowering but that of essential oil was increased after flowering.

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Perception of Radiological Technologists on Enacting of the Radiological Technologist Act in Korea (방사선사법의 제정을 위한 인식조사)

  • Lim, Chang Seon;Jin, Gye Hwan
    • Journal of the Korean Society of Radiology
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    • v.12 no.2
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    • pp.245-252
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    • 2018
  • In this study, we investigated the differences in the perception of radiological technologists to identify the main contents to be reflected in the enacting of the radiological technologist act and the necessity of the radiological technologist act. In the results of perception surveys conducted on the subjects of radiological technologists about the enacting of the radiological technologist act, the priority over "Somewhat satisfied" is the enacting of the radiological technologist solo act (90.1%), and as for tasks of radiological technologists, there are legalization of contrast media injection (85.8%), legalization of medical radiation policy deliberative committee (85.8%), legalization of radiological technologist ethics committee (80.9%), legalization of Compulsory subscription (71.6%), etc. In the results of the perception survey for radiologists about the enactment of the radiological technologist act, the priority above "Neither satisfied nor dissatisfied" includes the enacting of the radiological technologist act (100%), legalization of medical radiation policy deliberative committee (97.1%), and legalization of radiological technologist ethics committee (95.1%), and as for the tasks of radiological technologists, there are legalization of "contrast media injection" (95.1%), and the necessity of Radiological Education and Evaluation (94.34), etc. The radiological technologist act is considered a top priority and there is a difference in importance according to the individual agenda. This can be used as a data to determine the logical basis and policy direction of the establishment of the radiological technologist act.