• The Mathematical Education
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• v.50 no.3
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• pp.285-308
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• 2011

The objective of this study is to review how researches on mathematics education are being conducted currently in Korea and overseas and to examine the current state of domestic researches on mathematics education from a broader view. Although many efforts have been made to understand trends in researches on mathematics education, there have been few in depth studies on research trends in overseas or for comparison between domestic and overseas trends. Thus, this study classified and analyzed 181 domestic articles between 2005 and 2009 in the journals and and 201 overseas articles in the journals and according to year, research area, research contents, school level, research method, and key words using the PME classification system with some modification. Through these analysis, we examined research trends on secondary mathematics education in Korea and overseas. The research findings are as follows. First, 'teaching learning process' was a spotlight area both at home and overseas, and 'realistic mathematics' and 'social cultural subjects' were not covered much either at home or overseas. 'Mathematical communication' occupied a very small portion in Korea but was a highly interesting area in overseas research. Second, research contents of interest were different between Korea and overseas. Research on general area was the mainstream. But geometry and statistics were mainly studied in Korea and algebra and analysis in overseas. Third, research related to middle school was twice more than that related to high school in Korea, But, research related to middle school was the same as high school in overseas. Fourth, qualitative research was the absolute majority both at home and overseas, and philosophical didactical analysis was used only in Korea. Fifth, the order of key words were problem solving - teacher - curriculum - creativity - textbook in Korea, but teacher - teaching - semiotic - affective factor - proo f- problem solving - technology in overseas.

• Korean Journal of Microbiology
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• v.31 no.2
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• pp.148-156
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• 1993

Kinetic parameters of purine nucleoside phosphorylase (PNP) from Saccharomyces cerevisiae were measured. The Michaelis constants determined for substrates of the enzyme were $ 2.0 * 10^{-4}$ M for inosine, $2.0 *10^{-3}$ M for deoxyinosine, $ 2.0 * 10^{-5}$ M for guanosine and $2.0 10 ^{-5}$ M for deoxyguanosine. According to the ratio of relative $K_{cat}$Km, substrate specificity of each nucleoside was in the order of guanosine or deoxyguanosine, inosine and deoxyinosine. Cosubstrate, phosphate, revealed downward curvature in Lineweaver-Burk plot at high concentrations, indicating a negative cooperativity between subunits. The inhibition constants for purine analogs were measured to be $ 6 * 10^{-4}$ M for formycin B as the competitive inhibitor of inosine, $ 9 * 10^{-6}$ M for guanine as the competitive inhibitor of guanosine, $2 * 10^{-4}$ M for hypoxanthine as the non competitive inhibitor of guanosine and $4.5 * 10 ^{-4}$ M for 6-mercaptopurine as the non competitive inhibitor of guanosine. Alternative substrates, guanosine, deoxyguanosine and adenosine were found to act as competitive inhibitors with Ki values o $f^ 2.0 * 10 {-5}$ M, $2.6 * 10^{-5}$ M and $8.5 * 10 ^{-4}$ M, respectively, when inosine was the variable substrate. Guanosine and deoxyguanosine were also observed as competitive inhibitors with the Ki values of $1.8 * 10^{-5}$ M and $ 3.0 * 10^{-5}$ M, respectively, when deoxyinesine was the variable substrate. The results of alternative substrate sstudies suggested that a single enzyme acted on different nucleosides, inosine, deoxyinosine, adenosine, guanosine and deoxyguanosine.e.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.416-424
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• 2019

In Korea, press concrete in basements is mainly applied using plain concrete. This system has undesirable defects such as cracks caused by plastic shrinkage and irregular temperature distribution. To solve this problem, metal lath and fibers have been used in the past. However, they have not been effective in controlling cracks. This study analyzed the reduction of plastic shrinkage cracking for press concrete using various admixtures in a basement has been. In the air contents test, the specimens with various admixtures showed air contents similar to plain concrete (4.5±1.5%). The specimens using silica fume, super plasticizer agent, and SBR showed higher compressive strength by about 10-15% than plain concrete. Cracking decreased when the MC, super plasticizer, and SBR were added. When MC was used in the concrete, the plastic shrinkage did not occur.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.280-289
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• 2014

Purpose: This study was conducted in order to determine the stimulation variables which should be considered when neuromuscular electrical stimulation (NMES) is applied for a muscle under the normal innervation to minimize muscle fatigue and increase force-generating ability. Methods: A total of 23 healthy men participated in the study and all subjects were randomly assigned to the 1:1 group, 1:3 group, 1:5 group, and control group with on-off ratio of NMES. The subjects performed a fatigue task, consisting of 10 times of isometric contraction sustained by NMES. NMES using Russian current stimulation was applied to muscle fatigue and divided into three sessions by pulse frequency (10 bps, 30 bps, 90 bps). The EMG was recorded using an MP 100 system from the quadriceps femoris muscle in four groups. Results: The differences of delta MdF and delta MF of between on-off ratio groups of 10 bps, 30 bps, and 90 bps pulse frequencies were very significant (p<0.05). According to the results of post hoc of 10, 90 bps, it was greater in the 1:1 group and the 1:3 group compared with the 1:5 group, and no fatigue was observed in the control group. In 30 bps, it was greater in the 1:1 group compared with 1:3, 1:5, and control group (p<.05). Conclusion: Among NMES variables to minimize muscle fatigue, the larger on-off ratio by pulse frequency showed the lower muscle fatigue. Therefore, on-off ratio needs to be great enough, and will be more efficient with the frequency 30 bps rather than of 10 bps and 90 bps.

• Fashion & Textile Research Journal
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• v.19 no.5
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• pp.608-619
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• 2017

In this research, we analyze jackets from the Paris Haute Couture Collection from 2000 S/S~2015 F/W to investigate how shape, tailoring component, and design of jackets have changed. Our analysis of 2,493 jackets from the collection shows that the hour-glass silhouette was the most popular among silhouettes and that standard-length was the most popular jacket length. Such jacket shape expresses the natural beauty of human body. Regarding Tailoring Components, our analysis shows that tight sleeve and natural shoulder line, which is neither too wide, padded, nor low, were prevalent. The analysis also shows that tailored collar and button closure were the most common. Tight sleeve and natural shoulder line, which fit the body outline, allow the silhouette to show natural curves of the human body. As for jacket design, popular colors differed by season, but single-colored jackets prevailed, and woven was the most used material. Since 2000, the most favored form of jacket in women's fashion was a standard-length jacket with an hour-glass silhouette, tight sleeve, natural shoulder line, and tailored collar. This suggests that jackets emphasizing natural curves of the body were favored. Overall, silhouette, length, sleeve, and shoulder line remained consistent while collar and closure varied. This indicates that collar and closure method play a significant role in changes in fashion. Seasonally, elements of shape, tailoring component, and design coexist, but once the shape is determined, the tailoring component and design change in relation to each other.

• Journal of the Korean Society of Food Culture
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• v.1 no.3
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• pp.231-247
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• 1986

Age specific characteristics in Korean diet and their changes were analyzed with the demand model including the number of family members by age group as independent vasiables Urban household budget data, 773 household data in 1977 and 947 household data in 1983, was applied to the demand model. A series of F-test was carried out to set up the age groups by food item. The main results can be summarized as follows; 1. Food consumption patterns are remarkably different between 0-13 years old age generation and over 40 years old generation. The 0-13 years old generation reveals higher preference for milk, wheat product, fruit and milk and lower preference for rice and vegetable than any other age generation. This characteristics of the childhood diet has been formed In the generation born after 1970's and thus will be reserved as their generational characteristics. On the other hand, over 40 years old age group prefers rice and fish to fruit, milk and wheat product. Therefore we can conclude that over 40 years old age group maintains the traditional Korean diet pattern. 2. The preference for fish is low. in 20-30 years old age group than in any other age group and wheat product is Preferred highest in 6-13 years old age group of all age groups. Meanwhile the most remarkable change In food consumption pattern is shown in meats and vegetables. Namely in 30 40 years old age group the preference for meat has increased substantially and that vegetable has decreased to a great extent. 3. The declining per capita consumption of rice spreads like a wave to higher age. groups, but over 40 years old age group bas played an important role in reducing the decreasing rate of rice consumption. In order to restrain the declining rice consumption a special integrated food policy is required to induce rice consumption in less 30 years old generation.

• Korean Journal of Human Ecology
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• v.8 no.2
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• pp.355-362
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• 1999

The purpose of this study is focused on the quality of Kimchi by sensory evaluation in 67 research papers published by 8 kinds of food & nutrition related Korean journals from $1970{\sim}1995$. The results are summarized as follows : 1) Among 126 research papers on Kimchi, sensory evaluation results were shown in 67 papers. 2) The numbers of panelists for sensory evaluation were $10{\sim}12$ in 32 papers, $7{\sim}9$ in 15 papers, and $4{\sim}6$ in 6 papers. 3) The method of sensory evaluation applied was scoring test in all 67 papers. Among them, 25 papers utilized 5-points scale, 16 papers 9-points scale, and 11 papers 7-points scale evaluation. 4) Evaluated sensory characteristics were taste, texture, odor, appearance & color, and others. Sourness, salty, and carbonic taste in taste; hardness, crispness, and toughness in texture; moldy, acidic, and grassy odor in odor were the most frequently tested characteristics. 5) Fermentation/storage periods, fermentation/storage temperature, and concentration of salt/time of soaking in salt solution were the most frequently tested variables. 6) To evaluate the statistical difference, 31 papers applied F-test, and 9 papers were applied Duncan's multiple range test to determine which samples are significantly different from others. In 6 papers, correlation coefficients were calculated between sensory evaluation scores and the results of mechanical determinations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.3
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• pp.1359-1369
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• 2012

In the case of using pile foundation to support bridge abutments on soft ground, the soft ground often causes serious troubles such as lateral movement of bridge abutments by lateral surcharges. In this paper, we investigated and measured the amount of strain of a bridge abutment in the south-western part of Korea. To check the stability and possibility of lateral movement of the bridge abutment, we used the four analysis methods and compared those results; lateral movement index, index for decision of lateral movement and infinite element analysis method. We performed soil and ground tests to fine the causes of the strain and lateral movement. After reviwing several types of repair methods, we suggested the anker reinforcement method along with surcharge process method as a proper repair and rehabilitation of the bridge abutment. Our investigation by through the infinite element analysis method confirmed the effectiveness of the anker reinforcement method allong with the surcharge process method.

• Journal of radiological science and technology
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• v.22 no.2
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• pp.33-39
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• 1999

This paper included a data analysis of the unit of medical devices using mainternance recording card that had medical devices of unit failure mode, hospital of failure mode and MTBF. The results of the analysis were as follows : 1. Medical devices of unit failure mode was the highest in QC/PM such A hospital as 33.9%, B hospital 30.9%, C hospital 30.3%, second degree was the Electrical and Electronic failure such A hospital as 23.5%, B hospital 25.3%, C hospital 28%, third degree was mechanical failure such A hospital as 19.5%, B hospital 22.5%, C hospital 25.4%. 2. Hospital of failure mode was the highest in Mobile X-ray device(A hospital 62.5%, B hospital 69.5%, C hospital 37.4%), and was the lowest in Sono devices(A hospital 16.76%, B hospital 8.4%, C hospital 7%). 3. Mean time between failures(MTBT) was the highest in SONO devices and was the lowest in Mobile X-ray devices which have 200 - 400 failure hours. 4. Anverage failure ratio was the highest in Mobile X-ray devices(A hospital 31.3%, B hospital 34.8%, C hospital 18.7%), and was the lowest in Sono(Ultrasound) devices (A hospital 8.4%, B hospital 4.2%, C hospital 3.5%). 5. Failure ratio results of medical devices according to QC/PM part of unit failure mode were as follows ; A hospital was the highest part of QC/PM (50%) in Mamo X-ray device and was the lowest part of QC/PM(26.4%) in Castro X-ray. B hospital was the highest part of QC/PM(56%) in Mobile X-ray device, and the lowest part of QC/PM(12%) in Gastro X-ray. C hospital was the highest part of QC/PM(60%) in R/F X-ray device, and the lowest a part of QC/PM(21%) in Universal X-ray. It was found that the units responsible for most failure decreased by systematic management. We made the preventive maintenance schedule focusing on adjustement of operating and dust removal.

• Journal of Korean Academy of Nursing
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• v.48 no.3
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• pp.362-374
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• 2018

Purpose: This study aimed to develop a triage competency scale (TCS) for emergency nurses, and to evaluate its validity and reliability. Methods: Preliminary items were derived based on the attributes and indicators elicited from a concept analysis study on triage competency. Ten experts assessed whether the preliminary items belonged to the construct factor and determined the appropriateness of each item. A revised questionnaire was administered to 250 nurses in 18 emergency departments to evaluate the reliability and validity of the scale. Data analysis comprised item analysis, confirmatory factor analysis, contrasted group validity, and criterion-related validity, including criterion-related validity of the problem solving method using video scenarios. Results: The item analysis and confirmatory factor analysis yielded 5 factors with 30 items; the fit index of the derived model was good (${\chi}^2/df=2.46$, Root Mean squared Residual=.04, Root Mean Squared Error of Approximation=.08). Additionally, contrasted group validity was assessed. Participants were classified as novice, advanced beginner, competent, and proficient, and significant differences were observed in the mean score for each group (F=6.02, p=.001). With reference to criterion-related validity, there was a positive correlation between scores on the TCS and the Clinical Decision Making in Nursing Scale (r=.48, p<.001). Further, the total score on the problem solving method using video scenarios was positively correlated with the TCS score (r=.13, p=.04). The Cronbach's ${\alpha}$ of the final model was .91. Conclusion: Our TCS is useful for the objective assessment of triage competency among emergency nurses and the evaluation of triage education programs.