• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.15-17
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• 1957

1. Preparation of Titanium tetrachloride; The following precesses were strictly followed as the preliminary step to obtain pure $TiOCl_2$, titanyl chloride; First, pure Titanium Oxide mixed with carbon is rolled into pills. After drying up perfectly, these pills are heated at 900∼1000${\circ}C$. And then the pills are subjected to the flow of $Cl_2$ gas in a quartz tube heated to 900-1000${\circ}C$. Thus Titanium tetrachloride is obtained. 2. Preparation of $TiOCl_2$ ; Yellowish trobrown solution is made by pouring 80 g of conc. HCl (sp.gr. 1.19) to 45 gr of Titanium tetrachloride (approx. 2 times of theoretical amount). Then this solution is kept settled for 5-days in a desiccator filled with phosphorous pentoxide at room temperature. As the colorless amorphous solid thus obtained is washed with aceton, 36.5 g of the pure salt are obtained. 3. Determination of composition. The analysis of the sample taken from the deposit desiccated gives the following data; (A) Qualitative analysis; a) $Ti(OH)_4$ is precipitated by adding NaOH in water solution of the salt. b) Adding $AgNO_3$ solution, the water solution of the salt gives white precipitate of AgCl. c) When acid and $H_2O_2$ are added, the solution turns its color to redish brown (This proves that $TiO^{++}$ was converted into $TiO^{++}$ by oxidation of $H_2O_2$. (B) Quantitative analysis; a) $Ti(OH)_4$ precipitated by $10{\%}$ NaOH isalitatsubjected consecutively to the filtration and ignition in porcelain crucible at approx. 1000${\circ}C$. , then $TiO_2$ thus formed is weighed and calculated into Ti content. b) Chlorine involved in water solution of the salt is determined by Vorhardt method. Result: The values obtained from previous analysis, devied by their atomic weight gives the following composition: Ti : Cl = 1 : 2 Therefore $TiOCl_2$ should be given as its molecular formula. 4. Summary. When $TiCl_4$ is additated into conc. HCl, $TiO^{++}$ formed exists as a stable form, and forms $TiOCl_2$. However $TiOCl_2$ is unstable to heating. When the temperature is raised to $65{\circ}C$the decomposition of the solution is accelerated, and gives $TiO_2$ aq. $TiOCl_2$ in addition is highly hygroscopic.

• Journal of Digital Convergence
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• v.15 no.8
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• pp.455-463
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• 2017

Background/Objectives: The purpose of the study is to derive a goal usable in the field by exploring the case management success experiences of case managers. Civil case managers state that what is still important in case management practice is qualitative change made in the practice process. Therefore, the study will deal with detailed contents about case management that civil domain case managers consider to be important. Methods/Statistical analysis: For data collection, the study used focus group interview on 20 professional case management social workers and used Grounded theory method by Glaser for data analysis. The analysis of collected data consisted of a process of finding the categories and characteristics of the research problem. Findings: As a result of analysis, 4 categories, 10 subcategories, and 25 elements were derived for success experiences of case management practice. The categories were divided into satisfaction and ability improvement of client, case manager ability improvement, establishment of organization and environment function, and multilateral trust relationship strengthening. Improvements/Applications: The results of this study further clarified the goal of field case management practice and it was suggested as a plan to reflect on future case management related institutions evaluation.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.283-288
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• 2006

Discrimination of 5 rice cultivars (Sangjubyeo , Dongjinbyeo Simbaekbyeo , Hwamanbyeo , and Simbaek-hetero ) using metabolic profiling was carried out. Whole cell extracts from each cultivar were subjected to $^1H$ NMR spectroscopy. When spectral data were analyzed by principal component analysis, 5 cultivars were clustered into 3 groups: SJ, DJ + SB, and HM + SH. Thecultivars showed great difference in carbohydrate region of $^1H$ NMR spectra, suggesting that qualitative and quantitative differences in carbohydrate compounds play a major role in discrimination of the cultivars. In addition, it was readily possible to determine relative quantification of major carbohydrates including sucrose, glucose, maltose from spectral data of the cultivars. SJ showed 2 to 4 times higher content of maltose than the other rice cultivars. Overall results indicate that metabolic discrimination of rice cultivars using $^1H$ NMR spectroscopy combined by multivariate statistical analysis can be used for rapid discrimination of numerous rice cultivars and simple quantitative analysis system of major carbohydrate compounds in rice grains.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.6
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• pp.140-146
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• 2017

It is laser induced breakdown spectroscopy(LIBS) that enables qualitative and quantitative analysis of the elements contained in unknown specimen by comparing the wavelength characteristics of each element obtained from the spectral analysis of the standard specimen with the wavelength analysis results from unknown specimens. In this study, the applicability of LIBS to the analysis of major deterioration factors affecting concrete durability was experimentally analyzed. That is, the possibility of applying LIBS to the diagnosis of concrete deterioration by studying the quantitative detection of harmful deteriorating factors on chloride, sulfate and carbonated mortar specimens using LIBS was studied. As a result of LIBS test for each chloride and sulfate specimen, the LIBS spectral wavelength intensity of chlorine and sulfur ions increased linearly with increasing concentration. Carbon ion LIBS spectral wave intensities of carbonated specimens increased nonlinearly over the duration of carbonation exposure. From the above results, it can be partially confirmed that LIBS can be applied to the diagnosis of concrete deterioration. In case of concrete carbonation, it is presumed that carbon content is contained in the cement itself and is different from the detection of chloride and sulfate specimen. Therefore, it is considered that more various parameter studies should be performed to apply LIBS to concrete carbonation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.944-958
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• 2011

Soil hydraulic properties such as hydraulic conductivity or water retention which are costly to measure can be indirectly generated by soil pedotransfer function (PTF) using easily obtainable soil data. The field soil structure description which is routinely recorded could also be used in PTF as an input to reduce the uncertainty. The purposes of this study were to use qualitative morphological soil structure descriptions and soil structural index into PTF and to evaluate their contribution in the prediction of soil hydraulic properties. We transformed categorical morphological descriptions of soil structure into quantitative values using categorical principal component analysis (CATPCA). This approach was tested with a large data set from the US National Pedon Characterization database with the aid of a categorical regression tree analysis. Six different PTFs were used to predict the saturated hydraulic conductivity and those results were averaged to quantify the uncertainty. Quantified morphological description was successively used in multiple linear regression approach to predict the averaged ensemble saturated conductivity. The selected stepwise regression model with only the transformed morphological variables and structural index as predictors predicted the $K_{sat}$ with $r^2$ = 0.48 (p = 0.018), indicating the feasibility of CATPCA approach. In a regression tree analysis, soil structure index and soil texture turned out to be important factors in the prediction of the hydraulic properties. Among structural descriptions size class turned out to be an important grouping parameter in the regression tree. Bulk density, clay content, W33 and structural index explained clusters selected by a two step clustering technique, implying the morphologically described soil structural features are closely related to soil physical as well as hydraulic properties. Although this study provided relatively new method which related soil structure description to soil structure index, the same approach should be tested using a datasets containing the actual measurement of hydraulic properties. More insight on the predictive power of soil structure index to estimate hydraulic properties would be achieved by considering measured the saturated hydraulic conductivity and the soil water retention.

• Journal of Plant Biotechnology
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• v.45 no.4
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• pp.392-399
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• 2018

Fruits of 10 cultivars ('Blue Gold', 'Brigitta', 'Coville', 'Duke', 'Nelson', 'North Blue', 'Rancocas', 'Sierra', Sunrise, and 'Weymouth') of blueberries (Vaccinum corymbosun) were analyzed for characteristics, contents of total phenolic compounds and flavonoids and antioxidant activity in this study. Fruit weights ranged from 0.83 to 1.88 g. Total soluble solids concentration varied from 9.7 in 'Duke' to $16.6^{\circ}Brix$ in 'Sierra' with titratable acidities of 0.94 % in 'Sunrise' and 1.75% in 'Brigitta'. There are relatively high contents in 'North Blue' ($23.75mg\;GAE{\cdot}g^{-1}\;FW$) and low contents in 'Coville' ($17.15mg\;GAE{\cdot}g^{-1}\;FW$) in total phenolic compounds. Contents of total phenolic compounds were high in 'Nelson'($14.1mg\;QE{\cdot}g^{-1}\;FW$) and low in 'Duke' ($10.1mg\;QE{\cdot}g^{-1}\;FW$). Analysis of antioxidant activity of blueberry fruits showed that there were high acitiviites of ABTS+ radical scavenging in 'Rancoccas' (82.2%), 'Bluegold' (79.6%), and 'Nelson' (77.8%), and high activities of DPPH radical scavenging in 'Rancocca' (76.0%), and high in hydroxy radical scavenging in 'Nelson' (73.0%). Quantification analysis method of qualitative data showed that 'Bluegold', 'Nelson', 'Northblue', and 'Rancocas' had high contents of phenol and flavonoid compounds, and activity antioxidants of berries. Blueberry cultivars selected by statistical quantification analysis can be utilized as valuable genetic resources for breeding of blueberry with high antioxidant activities in the future.

• Communications of Mathematical Education
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• v.26 no.2
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• pp.177-203
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• 2012

The purpose of this research was to look at whether small group drawing activities can be applied to learning content that combine mathematics and art, by analyzing the changes in $10^{th}$ grade students' interests in mathematics and particular features of their strategic thinking that were reflected in small group drawing activities using graphs and inequations. The results of the study are as follows: 1. The small group drawing activity using graphs and inequations demonstrated that students interests in mathematics could experience positive changes. 2. The small group drawing activity using graphs and inequations was effective in stimulating the students' strategic thinking skills, which are higher level thinking activities necessary for creating problem solving. As the students went through the whole process of accomplishing a complete goal, the students engaged in integrated thinking activities that brought understandings of basic graphs and inequations together, and were also found to use such higher level thinking functions needed in achieving creative problem solving such as critical thinking, flexible thinking, development-oriented thinking, and inferential thinking. 3. The small group drawing activity using graphs and in equations could be expected to constitute learning content that integrate mathematics and art, and is an effective solution in boosting students' strengths in mathematics by way of activities that consider students' unique cognitive and qualitative peculiarities and through integration with art.

• Journal of Korean Academy of Nursing
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• v.28 no.1
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• pp.7-16
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• 1998

Various difficulties and inconveniences arise from having a mentally handicapped child in a family and these place many demands on mothers. There are few studies in Korea on these demands nor on what mothers go through with their mentally handicapped daughters' menarche and puberty. The purpose of the study was to examine the experiences of mothers of mentally handicapped daughters, as it relates to their daughters' menarche and the beginning of puberty. With indepth interviews, both in person and by telephone and participant observation the study used a qualitative research methodology to attempt to understand the experiences of these mothers. The data were gathered from October 1995 to April 1996. The subjects for the research included nine mothers of mentally handicapped daughters whose ages ranged from 12 to 18 and who attended one of three special schools located in either Inchon or Seoul. The data were recorded and analyzed : meaningful statements were grouped according to subjects raised by the mothers. Content Analysis was also applied to identify similar content and confirm common experiences. and to highlight concepts and categorized them. The results of this study are as follows. Five categories were identified : mothers' emotional responses to their mentally handicapped daughters' menarche and menstration were of severe despair accompanied by anxiety, guilt, fear, anguish, shame and pity because the mothers were afraid their daughters would not be able to use appropriate hygienic measures during menstration and the mothers felt heavily burdened in having to look them. The mothers also had negative feelings about their daughters' physical development. The experience of mothers related to their daughters' possibilities for marriage and pregnancy were of powerlessness, distress, withdrawal, fear. pity and desperation and they were afraid that their daughters might be violated sexually. The mothers rejected the possibility of marriage and pregnancy for their daughters and instead planned very restricting futures for them. The mothers used various coping methods to bring meaning to their lives. Because the negative emotional responses of the mothers. nurses need to work to empower mothers to overcome these negative responses. Sex education can also play an important role especially for the daughters especially through the use of visual aids. Further, nurses should understand the tearing difficulties of mentally handicapped daughters, what mothers need and also what they experience with their mentally handicapped daughters. In conclusion, nurses should understand the negative experiences of the mothers in relation to their mentally handicapped daughters' menarche, help the mothers cope with the negative. emotions through real life education and counselling. In addition, there is a need for nursing interventions and an administrative system which will minimize the prejudices of society towards handicapped people.

• Safety and Health at Work
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• v.10 no.3
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• pp.377-383
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• 2019

Objectives: Exposure to fine particles in urban air has been associated with a number of negative health effects. High levels of fine particles have been detected at underground stations in big cities. We investigated the exposure conditions in four occupational groups in the Stockholm underground train system to identify high-exposed groups and study variations in exposure. Methods: $PM_1$ and $PM_{2.5}$ were measured during three full work shifts on 44 underground workers. Fluctuations in exposure were monitored by a real-time particle monitoring instrument, pDR, DataRAM. Qualitative analysis of particle content was performed using inductively coupled plasma mass spectrometry. Nitrogen dioxide was measured using passive monitors. Results: For all underground workers, the geometric mean (GM) of $PM_1$ was $18{\mu}g/m^3$ and of $PM_{2.5}$ was $37{\mu}g/m^3$. The particle exposure was highest for cleaners/platform workers, and the GM of $PM_1$ was $31.6{\mu}g/m^3$ [geometric standard deviation (GSD), 1.6] and of $PM_{2.5}$ was $76.5{\mu}g/m^3$ (GSD, 1.3); the particle exposure was lowest for ticket sellers, and the GM of $PM_1$ was $4.9{\mu}g/m^3$ (GSD, 2.1) and of $PM_{2.5}$ was $9.3{\mu}g/m^3$ (GSD, 1.5). The $PM_1$ and $PM_{2.5}$ levels were five times higher in the underground system than at the street level, and the particles in the underground had high iron content. The train driver's nitrogen dioxide exposure level was $64.1{\mu}g/m^3$ (GSD, 1.5). Conclusions: Cleaners and other platform workers were statistically significantly more exposed to particles than train drivers or ticket sellers. Particle concentrations ($PM_{2.5}$) in the Stockholm underground system were within the same range as in the New York underground system but were much lower than in several older underground systems around the world.

• The Mathematical Education
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• v.60 no.2
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• pp.173-190
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• 2021

Education for Sustainable Development is an imperative mean to achieve the sustainable development which is the key idea that meets the needs of both present and succeeding generations by reconciling environmental protection, social development and economic growth. This study addressed the following question. First, what is the overall structure of the ESD contents presented in the textbooks? Second, How are the sub-contents of ESD distributed in the textbooks? Lastly, How are the ESD contents connected to mathematics in the textbooks? For this purpose, the contents in the elemtentary mathematics textbooks from 1^st to 6^th grades were analyzed at both macro and micro levels through quantitative and qualitative research methods. As results, contents related to environmental, social, and economic dimensions were presented from the first grade. The contents were involved the mathematics content domains of Numbers and Operations, Data and Possibilities, and Patterns. However, the contents were presented intensively in middle and high grades, and environmental topics accounted for a high proportion. Among the activities related to ESD, many were focused on solving problems mathematically while some were presented to solve problems as well as to consider sustainability through the activities. Based on the results, the study aims to provide implications for the direction of mathematics education for sustainable development in elementary school.