• Analytical Science and Technology
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• v.32 no.6
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• pp.225-232
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• 2019

Traceability establishment in chemical measurements is a like a linkage established through an unbroken chain from the measured results to the international system (SI) of units. The primary process for traceability establishment is the purity assignment of a target material to be measured. In this study, we studied the purity assignment of 17α-hydroxyprogesterone (17-OHP). The presence of 17-OHP is indicative of congenital adrenal hyperplasia (CAH) and it builds up due to the deficiency of 21-hydroxylase and 11β-hydroxylase enzyme in the human blood. The purity assignment of 17-OHP was performed by the mass balance method, in which the impurities are categorized into four classes: total related structural impurities, water, residual organic solvents, and nonvolatiles/inorganics. The total related structural impurities were characterized by HPLC-UV; water content was determined by Karl-Fisher coulometer; and the total residual solvents and nonvolatiles/inorganics were determined by TGA. The purity of 17-OHP from a commercial manufacturer was calculated as 993.30 mg/g, and the expanded uncertainty was 0.58 mg/g. The proposed method was validated by uncertainty evaluation and comparing with the actual value of purity.

• Animal cells and systems
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• v.13 no.3
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• pp.351-356
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• 2009

Ciliates are undoubtedly one of the most diverse protozoans that play a significant role in ecology. However, molecular examination, based on comparing the DNA sequences, has been done on a limited number of the species. Because most ciliates are uncultivable and their population sizes are often too small, it is usually difficult to obtain sufficient genomic DNA required for PCR based experiments. In the present study, we evaluated the effectiveness of four commercial DNA extraction procedures that extract high quality genomic DNA from a single ciliate cell. It was discovered that RED Extract-N-$Amp^{TM}$ PCR kit is the best method for removing PCR-inhibiting substances and minimizing DNA loss during purification. This method can also amplify more than 25 reactions of PCR. In addition, this technique was applied to single cells of 19 species belonged to 7 orders under 5 classes that isolated from mixed natural populations. Their small subunit ribosomal DNA (SSU rDNA) was successfully amplified. In summary, we developed a simple technique for the high-yield extraction of purified DNA from a single ciliate cell that may be more useful for rare ciliates, such as tiny and uncultivable marine microbes.

• Korean Journal of Community Nutrition
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• v.11 no.2
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• pp.161-171
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• 2006

This study was carried out to investigate the dietary attitudes and nutritional status of preschool children in different income levels in Busan. The survey was conducted from November 1 to November 30, 2004 by questionnaires mid data analyzed by the SPSS program. The results are summarized as follows: The Kaup index of the upper income class group was higher than that of the other income classes. In the middle income class group, nutrition knowledge scores were higher than in any other income class. Sixty-four point nine percent of the upper income class children, 25.7% of the middle income class children and 15.7% of the low income class children had nutrition education experiences. Intake of protein was higher than that of the Korean recommended dietary allowances (RDAs) for children. In the upper income class group, intake of calcium was higher than in any other income class. Intakes of calcium and iron were lower than those of the RDAs in all children. Dietary attitude had positive correlation with frequency of breakfast, time for outdoor activity, and height and weight, and had negative correlation with frequency of fast food and time for watching television. Frequency of snack had positive correlation with frequency of fast food and time for watching television, but frequency of breakfast had negative correlation with those. These results indicate that nutrition education programs linking parents to children should be carried out to improve their nutritional status.

• Journal of the Korean Society for Library and Information Science
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• v.38 no.1
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• pp.121-141
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• 2004

This study is a case study with four classes of sophomore majoring in library ＆ information science in S woman's college, with a questionnaire, firstly to research the students' recognition of their experience on bibliotherapy and the time, their preference of the materials' genre for the bibliotherapy. usefulness of the bibliotherapy' subject, apply possibility into library work, and the field of science that must be supplemented for the bibliotherapy. Secondly. a direction of development is presented analyzing researched contents and lecture experiences, centering on the factors that should be complemented and prepared in studying or lecturing the course of bibliotherapy as a school subject in the field of library ＆ information science hereafter.

• Molecular & Cellular Toxicology
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• v.1 no.3
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• pp.157-163
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• 2005

Because of their widespread occurrence and substantial biological activity, halogenated aromatic hydrocarbons are one of the important classes of contaminants in the environment. We have performed comparative molecular field analysis (CoMFA) on structurally diverse ligands of Ah (dioxin) receptor to explore the physico-chemical requirements for binding. All CoMFA models have given $q^{2}$ value of more than 0.5 and $r^{2}$ value of more than 0.83. The predictive ability of the models was validated by an external test set, which gave satisfactory predictive $r^{2}$ values. Best predictions were obtained with CoMFA model of combined modified training set ($q^{2}=0.631,\;r^{2}=0.900$), giving predictive residual value = 0.002 log unit for the test compound. We have suggested a model comprises of four structurally different compounds, which offers a good predictability for various ligands. Our QSAR model is consistent with all previously established QSAR models with less structurally diverse ligands. The implications of the CoMFA/QSAR model presented herein are explored with respect to quantitative hazard identification of potential toxicants.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.240-244
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• 2008

This paper presents an EMG-based wireless and wearable computer interface. The wearable device contains 4 channel EMG sensors and is able to acquire EMG signals using signal processing. Obtained signals are transmitted to a host computer through wireless communication. EMG signals induced by the volitional movements are acquired from four sites in the lower limb to extract a user's intention and six classes of wrist movements are discriminated by employing an artificial neural network (ANN). This interface could provide an aid to the limb disabled to directly access to computers and network environments without conventional computer interface such as a keyboard and a mouse.

• Journal of the Korean housing association
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• v.16 no.1
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• pp.1-9
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• 2005

The purpose of this study is to scrutinize forefathers' standpoint on architectural planning by peering into their literature. Dongkukyisangkukjib which contains works about daily life of Lee Gyu-Bo, a great writer in the middle of Koryo, reveals well people of Koryo' thought on architecture, if we have a interest in a building space. The book holds his general viewpoint on architecture and documents about the remarkable houses he and his friends visited. Then we can know, through it, general thought on architecture of the upper classes in those days. Lee Gyu-Bo considered a house the other self of its owner and connected buildings with personality of their owner. 0 architectural process and architectural planning, buildings were shown variously by reflecting owner's value on architecture. Unlike Chosun era, people of Koryo prefer unlimited thinking to form or order. Therefore in construction especially such as a pavilion, there were many experimental tries which reflected owners' thought. Particularly we could estimate people of Koryo' conception of architectural design through a work of Lee Gyu-Bo, Saryunjungky, a document about a pavilion carrying four wheels, which describes concretely contents of architectural planning such as a planning of space, module, and intention.

• Journal of the Korean earth science society
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• v.23 no.8
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• pp.632-639
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• 2002

The purpose of the study is to develop a scoring rubric for students’ mind maps. The participants of this research were students in two fourth-grade classes selected from an elementary school in Pyungtaek-shi. After receiving basic training, students developed mind maps four times while teaming two science units. In order to score the mind maps, a scoring rubric was developed. To estimate the reliability of the rubric, selected mind maps were marked by three teachers and correlational coefficients were calculated with SPSS. As a result of the study, a scoring rubric consisted of three domains, central circle, branches, and expression were developed. The reliability of the rubric is proven to be high to very high.

• Journal of The Korean Association For Science Education
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• v.18 no.3
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• pp.297-301
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• 1998

To investigate the 7th graders' ideas on inquiry, researchers analysed the titles of inquiry report, which were submitted as summer vacation homework. The subjects were four classes of 141 thirteen year old boys and girls in a school in Seoul. After analysing the titles of student's report, researchers classified the titles into 9 types according to the clarity and the nature of variables in the titles. The fact that few students represented the variables in the report title and most of the variables used were categoric was found.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.33-33
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• 2013

We are developing empirical space weather (solar flare, solar proton event, and geomagnetic storm) forecast models based on solar data. In this talk we will review our main results and recent progress. First, we have examined solar flare (R) occurrence probability depending on sunspot McIntosh classification, its area, and its area change. We find that sunspot area and its increase (a proxy of flux emergence) greatly enhance solar flare occurrence rates for several sunspot classes. Second, a solar proton event (S) forecast model depending on flare parameters (flare strength, duration, and longitude) as well as CME parameters (speed and angular width) has been developed. We find that solar proton event probability strongly depends on these parameters and CME speed is well correlated with solar proton flux for disk events. Third, we have developed an empirical storm (G) forecast model to predict probability and strength of a storm using halo CME - Dst storm data. For this we use storm probability maps depending on CME parameters such as speed, location, and earthward direction. We are also looking for geoeffective CME parameters such as cone model parameters and magnetic field orientation. We find that all superstorms (less than -200 nT) occurred in the western hemisphere with southward field orientations. We have a plan to set up a storm forecast method with a three-stage approach, which will make a prediction within four hours after the solar coronagraph data become available. We expect that this study will enable us to forecast the onset and strength of a geomagnetic storm a few days in advance using only CME parameters and the WSA-ENLIL model. Finally, we discuss several ongoing works for space weather applications.