• Journal of ILASS-Korea
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• v.3 no.4
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• pp.43-49
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• 1998

In order to clarify the effect of equivalence ratio and kinds of fule in flame structure, a numerical simulation of triple flame developed in a co-flowing methane-air and air stream was carried out by the elementary chemical reaction mechanism. The following conclusions were obtained. Equivalence ratio at which the apparent burning velocity is maximum is a little larger than that of the one-dimensional premixed flame. Apparent burning velocities are two times higher than that of the one-dimensional premixed flame for the methane-air. The flame thrusts out forward in the downstream of the boundary between mixture and air stream, and a part of the flow is bent and forks out in this protruding flame so that a triple flame is originated; this triple flame is composed of fuel rich and lean premixed flame branches and a diffusion flame branch. Near the equivalence ratio at which the burning velocity of rule-dimensional premixed flame is the largest the effect of one-dimensional premixed flame becomes large and the fuel rich premixed flame advances and becomes vertical to the flow direction.

• The Journal of Pediatrics of Korean Medicine
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• v.23 no.3
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• pp.143-153
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• 2009

Objectives The purpose of this study is to get the basic information from patients how much they understood about their medication and also to know whether patients are making reasonable drug choice between Health Functional Foods and Herbal medicine. Methods 500 questionnaires were handed out to the parents of students in two elementary schools located in OO, Junlabukdo province. 421 questionnaires were completed to be evaluated. Results Among 421 subjects, 53.0% were female, and 47.0% were male. The percentages of the subjects consuming Health Functional Foods and herbal medicine were67.7% and 67.8%, respectively. Among those people who consumed Health Functional Food, 44.1% were using nutritional supplements, red ginseng or ginseng products (26.9%), chlorella products (11.5%), and plum extract products (7.7%). As for the reason to consume Health Functional Foods were varied, but 'in order to be healthy, although currently displaying no illness.'(43.0%) were the most responses among the given choices. On the other hand, the reason for consuming herbal medicine was 'In order to grow taller'(26.1%), 'In order to cure weak physical state frequently displaying common illnesses',(25.9%), and 'In order to cure diseases.'(23.3%). For the questions about effectiveness after consumption,the 69.9% subjects said that it seemed to be effected, and that % was slightly higher than that of subjects with consuming Health Functional Foods(64.4%). For question concerning preferences between Health Functional Foods and herbal medicine, 57.5% chose herbal medicine, and this percentage was higher than that of Health Functional Foods(42.5%).As for the reasons of additional consumption of the Health Functional Foods, subject answered as 'Easy to consume.'(41,6%), which was the most common among the subjects consuming Health Functional Foods. On other hand, the subjects of herbal medicine answered as that herbal medicine is 'more effective'(45.7%), and 'more trustworthy in preventing side-effects.'(40.3%). After consumption of the herbal medication, only 3.9% of the subjects consuming either Health Functional Foods or herbal medicine had side-effects. The most common side-effects were 'dermal reaction' which is normally caused by Health Functional Foods and 'indigestion' problems caused by herbal consumption. Conclusions According to the 421 subjects those involved in study, the percentages of consuming Health Functional Foods(67.7%) and herbal medicine(67.8%) were similar. The most commonly consumed products were a type of Health Functional Foods which were the nutrition-supplying products. Ginseng or red ginseng products were the next commonly used products. Health Functional Foods were commonly consumed for preventing illness and maintaining health rather than any other purpose. In contrary, herbal medicines were more commonly consumed for purposes such as for growth or treating certain type of disease. As a result of consumption, more than half of both subject replied as 'satisfied'. As for the side effects, dermal reaction was the most common problem for those with consuming Health Functional Foods, while indigestion was the most common side effect from the subjects with consuming herbal medicine.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.861-868
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• 1996

Skeletal isomerization reaction known as exothermic reaction shows possible maximum yield of i-butene from n-butene at $110^{\circ}C$ over $Pt/MoO_3/SiO_2$. Compared with conventional catalyst such as silica, zeolite, alumina etc., $Pt/MoO_3/SiO_2$ demonstrates higher yield while by-products except 2-butene do not form. Faster H spillover rate over $Pt/MoO_3/SiO_2$ is demonstrated via isothermal reduction experiment at $110^{\circ}C$ compared to the rate over $Pt/MoO_3/Al_2O_3$. Overall isomerization rates are proportional to higher spillover rates from Pt onto $MoO_3$ surface. The skeletal isomerization reaction is composed of two elementary steps. First, carbonium ion formation over Pt crystallites by H spillover. Second, carbenium ion formation over $MoO_3$ followed by formation of i-butene. Moreover, it is suggested that H spillover step from Pt surface onto $MoO_3$ is assumed to be the rate determining step and control the overall isomerization rate.

• Journal of Educational Research in Mathematics
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• v.19 no.1
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• pp.63-80
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• 2009

This paper has a purpose to find out the important points about linguistic factors suited to the assessment purpose and mathematics teaching/learning that a word-problem sentence has to possess. We also examine the degree of understanding of sentence and the perceptive/emotional reactions of students toward two different kinds of word-problem sentences that have same mathematical contents, but different linguistic structures. The objects of this thesis are 124 students from the third to sixth grade in an elementary school. We execute assessment of simple-sentence-word-problem and complex-sentence-word-problem that have same mathematical contexts, but different linguistic structures. Then we have compared and examined their own process of solving the two types word-problems and we make up questionnaire and have an interview with them. The conclusions are as followings: First, simple-sentence-word-problem is more successful to suggest an information for solving a problem than complex one. Second, it is hard to find the strategy for solving a problem in complex-sentence-word-problem than simple one. Third, students think that suggested information and mathematical knowledge are different according to the linguistic structure in the process of perceiving the information after reading a word-problem. Fourth, in spite of same sentence type, the negative mental reaction is showed greatly to complex-sentence-word-problem even before solving a problem.

• Journal of Korean Home Economics Education Association
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• v.20 no.3
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• pp.231-258
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• 2008

The purpose of this study was to analyse the needs and recognitions of education to prevent children sexual abuse and to suggest the basic data for school prevent education program. For this purpose 1210 primary school teachers were suggested in Korea and finally 973 questionnaires were analysed. The results are as follows; First, fur the needs of education contents for children,'the reaction skills to crisis situation of sexual abuse' was most needed, and 'the types and cases of sexual abuse' and 'the legal regulations' were lowest. Second, for the recognitions of education forms for children, teachers thought the proper form that professional instructors outside school related sexual abuse in special education type, $1\sim2$ times per semester, to all years of children and parents. Third, the education contents and forms to prevent sexual abuse to children were significantly different by age, gender, carrier years, area for work, related training experience. Fourth, the retraining program chances for teachers and prevent education program for children using the National Common Basic Curriculum needs to be broad.

• Journal of the Korean Chemical Society
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• v.64 no.6
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• pp.371-378
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• 2020

The purpose of this study is to analyze the relationship between the eight topics in TIMSS 2019 8th grade chemistry domains and the Korea 2009 Revised Science Curriculum and the 2015 Revised Science Curriculum. For this purpose, four elementary and four secondary teachers participated in physics, chemistry, biology and earth science majors, and two science education experts participated in analyzing in which grades the content elements of the TIMSS 2019 science framework are covered in the Korean science curriculum. The study also analyzed whether the content of the Korean science curriculum matches the 246 items of 8th grade in the TIMSS 2019 assessment and reflects in which grades the eight topics are covered. The results of this study are as follows. First, among the TIMSS 2019 evaluation topics, topics not covered at all in the Korean middle school curriculum were periodic table, matter and energy in chemical reactions, the role of electrons in chemical bonds. Second, the topic of "the periodic table as an organizing principle for the known elements" needs to be introduced in the Korean middle school curriculum, and topics such as "familiar exothermic and endothermic reactions" and "factors affecting the reaction rates" need to be discussed in consideration of the flow of international curricula. Third, the next science curriculum should be structured so that the sequence of chemistry contents and scope, especially core concepts to be included in the elementary, secondary, and higher education curriculum is linked to continuity.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.4
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• pp.65-74
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• 2002

This Study was investigated operating condition of pyrolysis processing for sludge disposal in sewage treatment plant. Important parameters studied include running time of pyrolysis, run time of dry and pyrolysis processing, water content of sewage sludge, solids amount of sewage sludge(TS%), condition of pyrolysis temperature. Most degradation reaction of sewage sludge are first order, it assumed first order and elucidated the kinetics. This was the basis of characteristics analysis of sludge degradation mechanism. Also, with the increasing of temperature, how the yield of oil and char product change was observed, and the distribution of gas product components was observed. Main components of gas and carbon product are a little difference with pyrolysis temperature, but it consist of $CH_4$, $C_2H_4$, $C_3H_8$, $C_4H_{10}$, toluene, $C_6H_6$, $SO_2$, CO etc. The gas of $C_1-C_4$ yield increased along with degradation temperature of $670^{\circ}C$ and oil yield decreased of $C_6H_6$ and $C_6H_5OH$ with temperature of $600^{\circ}C$. Particularly, low value added char yield 134kg/t at $670^{\circ}C$, but increased to 194kg/t at pyrolysis temperature of $600^{\circ}C$. In the result of elementary analysis on it, it is mainly composed of carbon. From this fact, in pyrolysis of sludge, it comfirmed that carbonization reaction occur at high temperature well.

• Journal of Distribution Science
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• v.11 no.10
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• pp.47-53
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• 2013

Purpose - Six months have passed since the amendment of the SSM regulation law; however, as yet, there is no confirmed research or report on the effects of this amendment, which are indefinite. Further, there have been no attempts to study the effects of the SSM regulation law from the consumers' viewpoint, which is important because consumers are the main agents that are greatly influenced by the amendment law. Therefore, this study aims to investigate the consumers' attitude toward the SSM regulation law as well as the effects of the SSM regulation law on the changes in purchase behavior. Research design, data, and methodology - This study was initiated from four research problems that are linked to consumer reaction to the SSM regulation law. Research problem 1: What is the consumers' reaction (perception, attitude, and perceived fairness) to the SSM regulation law? Research problem 2: How do the consumers' reactions to the SSM regulation law differ by consumers' characteristics? Research problem 3: Could the SSM regulation law change a consumer's purchase behavior? Research problem 4: Is it necessary to amend the SSM regulation law? This study collected the data through the interview and survey of housewives for the purpose of solving the research problems. The interview was conducted as a pilot study for the field survey. We interviewed three housewives, who were: an employed housewife, a full-time homemaker, and a manager of a housewife club, respectively. We then conducted a field survey of 232 housewives who were housewife club members or elementary school parents in Chunghcheong-do. Results - We verified the reliability and validity of the data, and analyzed it to solve the research problems. The main findings of this study were as follows. First, consumers still have a positive attitude toward large discount chains and SSM, which has been the case since the law was introduced. Second, perceived risk of consumers associated with traditional markets and small neighborhood shops was low. Third, consumers think that amendments of the SSM regulation law are important, and they positively assess the satisfaction, necessity, and propriety of the law. Fourth, although the SSM regulation law caused inconvenience to consumers, this law did not have any influence on the usage frequency and the use-behavior of large discount chains. Finally, consumers reacted very negatively to the toughening up of the SSM regulation law. Conclusions - In short, consumers still have a positive attitude toward the SSM regulation law. However, this act did not have any influence on the use-behavior of large discount chains (General Super Market). Thus, policy making authorities require active communication and promotions to enhance the effect of the SSM regulation law. This study was of the nature of exploratory research, which did not focus on hypothesis testing, but on finding solutions to the research problems. Therefore, this study is no more than a simple data analysis. Future studies should attempt to investigate the actual effects of the SSM regulation law, on the basis of sufficient literature review and real sales data.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.41-48
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• 2000

A bacterial strain, designated as JK-43, producing extracellular cyclodextrin glucanotransferase (CGTase)[EC 2.4.1.19] was isolated from kimchi. The CGTase from isolated strain JK-43 showed the transglucosylation activity from soluble starch to L-ascorbic acid(AA) compared to those obtained from other strains. A main product formed by this reaction was identified as $2-O-{\alpha}-glucopyranosyl$ L-ascorbic acid(AA-2G) by testing its susceptibility to ${\alpha}-glucosidase$ hydrolysis, the HPLC profiles, and through the elementary analysis. the ${\beta}-CD,\;{\gamma}-CD$, potato starch and corn starch were identified to be suitable glucosyl donor for transglucosylation reaction on AA by CGTase. Acceptor specificity on AA-2G production was examined by use of AA, Iso-AA and AA-2P. Transglucosylation was observed toward AA-2P as well as AA and Iso-AA. The microorganism isolated from kimchi was identified as a strain of Bacillus sp. JK-43 based on the morphological, cultural, biochemical characteristics and partial 16SrDNA sequence analysis. The maximal CGTase production was observed in a medium containing 1.0% soluble starch, 1.0% yeast extract, 1.0% $Na_2CO_3\;0.1%\;K_2HPO_4,\;and\;0.02%\;MgSO_4{\cdot}7H_2O$ with initial pH 7.0. The strain was cultured at $37^{\circ}C$ for 26 hrs with reciprocal shaking.

• The Mathematical Education
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• v.42 no.3
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• pp.295-302
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• 2003

The purpose of this study is to make more reliable researches on the tendency of shirking from the mathematics by including those of the students in the other country, and there are a series of researches such as 'math-camp to raise the mathematical tendency of the students who make little progress in the study', 'establishment of factors causing the shirking tendency from the mathematics and development of the analyzing instruments for it' and 'study on the preference to each category of the school mathematics.' For this purpose, I used a test developed by the shirking tendency research team. I compared the average score and standard deviation between the Korean and the Australian students. As for the average score, that of the Australian elementary school students is about one point higher than the Korean students, and there was no remarkable difference in the deviation. Comparing the math-shirking tendency of the two groups, they show higher shirking tendency in the aspects of emotional and mathematical recognition that belong to the psychological and environmental sphere. And, as for an extent of association in difficulties according to each school grades, its degree of the Australian students is comparatively lower than that of the Korean students, therefore, the shirking tendency of the Australian students is intermediate level whereas that of the Korean students is the lowest. They show us a peculiar result in teacher factor. It is noteworthy in that the Korean students show a positive reaction in that factor, however, the Australian students show a comparatively weak reaction. It might be caused by a cultural difference. I also have compared the accumulated percentage according to each shirking tendency factors. It will not only be very efficient for teachers to establish a teaching plan but also a good data to understand the shirking tendency of each student. This will be a very good data for the planners of teaching policy to remedy the causes of shirking tendency. And, it will also be used effectively to write a new textbook. It has been uncommon that a psychological test is used in the research for the improvement of teaching and learning mathematics. In this aspect, I am sure that this study including the preceding research will be a good in studying the shirking tendency factors by using a psychological test. I believe that this research will be a help to grasp the outline of the shirking tendency and I will have to try continuously to make it be a reasonable and reliable study.