• Communications of Mathematical Education
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• v.36 no.4
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• pp.469-486
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• 2022

Counting occupies a fundamental and important position in mathematical learning due to its relation to number concepts and numeral operations. In particular, counting up to large numbers is an essential learning element in that it is structural counting that includes the understanding of place values as well as the one-to-one correspondence and cardinal principles required by counting when introducing number concepts in the early stages of number learning. This study aims to derive didactical implications by investigating the possibility of and the strategies for counting large numbers that is expected to have no students' experience because it is not composed of current textbook activities. To do this, 89 second-grade elementary school students who learned the three-digit numbers and experienced group-counting and skip-counting as textbook activities were provided with questions asking how many penguins were in a picture where 260 penguins were irregularly arranged and how to count. As a result of analyzing students' responses in terms of the correct answer rate, the strategy used, and their cognitive characteristics, the incorrect answer rate was very high, and the use of decimal principles, group-counting, counting by one, and partial sum strategies were confirmed. Based on these analysis results, several didactical implications were derived, including the need to include counting up to large numbers as textbook activities.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.279-286
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• 2009

This study carried out to find out feed value of barley plus pea mixture with different ratio and cutting date to got basic information when introduced the mixture as new cropping system in middle part of Korean peninsular. Dry matter (DM) yield increased as barley seeding rate was higher and showed the highest yield in the plots with barley 85% plus 15% ratio when harvested on May 16. There was no different in crude protein, available protein and digestible protein cutting on April 25 in every mixture, but the content increased with higher pea mixture rate after May 2. The content of acid detergent fiber (ADF) and neutral detergent fiber (NDF) increase coincided with higher barley rate and late cutting dates. But relative feed value (RFV) resulted in opposite trend. Higher pea ratio influenced increased content of total digestible nuterients (TDN), but decreased before May 9 cutting and increased after the next cutting regime. There was no statistical difference in P and Mg between sowing rate, but Ca increased at higher pea ratio and P, Ca, K decreased in all plots as harvests were delayed. The content of estimated net energy (ENE), net energy maintenance (NEM) and net energy gain (NEG) significantly increased with higher pea rate and earlier cutting. But net energy lactation (NEL) was no significant differences between seeding rates and cutting dates. In conclusion, mineral yield such as P, Ca, K and Mg showed the highest yield at barley plus pea ratio of 75 : 25 and energy yield of ENE, NEL, NEM, NEG and TDN was the highest at 85 to 15 mixture plots and DM yield, TDN yield, mineral yield such as P, Ca, K and Mg and energy yield of ENE, NEL, NEM, NEG were the highest on each treatment cutting on May 16.

• Korean Educational Research Journal
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• v.41 no.2
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• pp.25-53
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• 2020

Purpose: School safety has recently become an important issue. In order to make a school environment safer, surveillance cameras have been installed in the facilities. The number of installations has been increasing rapidly since they have been considered widely recognizable and highly effective. However, conflicts between faculty and staff in installing and operating the system have also been increasing. In terms of school safety, these individuals'' cooperation is more than necessary. It is judged that looking into how they perceive the system could provide us with some suggestions on how to manage the related issues. The purpose of this study is to understand the perspective of faculty over closed-circuit television (CCTV) and make suggestions by analyzing their actions. Approach: In order to achieve the research objectives, I surveyed administrative actions such as the processing of official documents and CCTV policies for teachers and administrative staff of public schools in the Sejong Office of Education. In addition, I analyzed the behavior of those managing personal information and school safety-related documents along with the degree of complying with the policies. Finding: First, the correspondence rate of documents was high when there were designated document processors. Second, the acceptance level of documents in preschool was relatively low when there were designated processors. Third, the degree of accepting the policies and complying with them was higher in newly established schools than in existing schools. I found differences in the perception of how to handle the CCTV operations and the related work among the two groups of participants. In addition, I made suggestions on how to resolve the conflicts between them. Value: In this study, the education authorities quantified and measured the recognition and acceptance of faculty and staff regarding CCTV at each school level. Results showed that the active role of education authorities can make positive changes in how faculty and staff perceive the CCTV system and the problems surrounding it through school administrative action. In this regard, these results are meaningful in reducing the conflicts among the two groups and improving the organizational culture.

• Journal of Chest Surgery
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• v.21 no.6
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• pp.1020-1029
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• 1988

The authors evaluated 153 patients who had undergone cardiac valve replacement between October 1979 and July 1988. The results are as follows: l. Out of 153 patients, there were 56 males and 97 females ranging from 15 to 62 years of age with a mean of 37 years. 2. Isolated mitral valve replacement took place in 82 patients, aortic valve replacement[AVR] in 16, double valve replacement[DVR] in 34, AVR combined with open mitral commissurotomy in 19, and tricuspid valve replacement[TVR] was done in 2 patients. 3. 153 patients had 187 prosthetic valves replaced with Ionescu-Shiley valves[16], Carpentier-Edwards[36], Bjork-Shiley[19], St. Jude Medical[108], and Duromedics[8]. 4. Our of 98 patients with atrial fibrillation[ 64% of a total 153 patients ] during the preoperative period, 22 patients recovered NSR[ 22/98, NSR recovery rate 22.4%] after valvular surgery and remaining 76 patients revealed persisting atrial fibrillation[76/153, 49.7% ]. 5. Preoperative episodes of systemic arterial embolization were attained in 9 patients[9/153, 6% ], and left atrial thrombi were confirmed in 22 patients intraoperatively[ 22/153, 14% ]. Of these, only one patient, however, demonstrated the correspondence of preoperative embolization and intraoperative existence of LA thrombi. 6. With mechanical prostheses, anticoagulant therapy was begun 48 hours after operation with sodium warfarin[2.5-5.0mg/day], maintaining the prothrombin time between 16 and 18 seconds or 30 to 50% of control values and continued for life. With tissue prostheses, sodium warfarin was continued for 3 to 6 months and converted into buffered ASA[ 325 mg/day ] for one year. 7. The mean follow-up for the survivors was 30.1 months, with a range from 3 months to 9 years. All suspected or confirmed thromboembolic episodes counted as events and occurred in 4 patients[ 1.04%/patient-year] with mechanical valve replacement. No persistent paralysis or death was noted. Late complications have not yet occurred in the patients with isolated MVR and AVR. 8. There were remarkable structural failures of tissue valves in 3 patients[ 1.9%/patient-year ], while no instance of failure of a mechanical valve. 9. There were 10 operative early deaths[10/153, 6.5%] and 5 late deaths[5/153, 3.3%]. Consequently, overall mortality was 9.8%[ 15/153] during follow-up period. 10. We currently favor using the St. Jude Medical valve in all patients requiring valve replacement except in those who can not take warfarin anticoagulation.

• Land and Housing Review
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• v.6 no.4
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• pp.195-213
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• 2015

Recently, there has been changing the housing rental market paradigm structure which has been increased the ratios of partly monthly rental ratios, because of increasing chonsei's price, the preference of monthly rental and the rack of chonsei's supply amount. This study had done a survey of 1,400 people for private and public rental residents by region and housing types during Dec. 2014. According to the result of survey, Market participant prospect strongly to change chonsei to monthly rental market structure and the reason of rising of chonsei's price is the preference of householder's monthly rental because of decreasing interest rate and the rack of chonsei's supply amount. The housing policy's proposal of the stability of low income class's housing and jense's price strongly recommended the expansion of public rental housing supply and the activation of private rental housing, the expansion of chonsei loan, housing boucher etx. The rental market policy for high income class have desired to market autonomy than public side's intervention, on the other hands, the rental market policy for low income class have strongly need to the public side's intervention such as the contiuneous long-term rental housing supply.

• Journal of the Korean Society of School Health
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• v.15 no.2
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• pp.249-261
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• 2002

This study was a research study to find out the real picture and practice of student obesity control by primary, middle and high school school nurses. The study sampled 196 school nurses working in the Busan City and Northern Gyungsang Province, who agreed on the purpose of the study. When it comes to the study process, at the meeting of the whole school nurses, the researcher explained the purpose of the study and asked them to complete questionnaires and return on the spot. The study is designed to provide basic data for school nurses in field to systematically and efficiently control student obesity by examining perception of school obesity control and the real picture or practice of obesity control as well as its problems. The study used SPSS 10.0 to analyze data. The results are as follows: Annual plans about obesity control appeared significant at the primary school, 89.3%, higher than 77.3% of the middle and high school(p<0.05). Annual project evaluation showed a significant difference by regions, 56.0% of metro cities vs. small cities(p<0.01). The number of measuring weight of obese students was higher at the primary school than at the middle and high school(p<0.05). Also small cities conducted the weight measurement more often than metro cities(p<0.001). Among the health education methods for obesity, counseling appeared statistically significant(p<.01). The health education showed a significant difference in more experienced school nurses. Among the educational media, environment postings were used at the primary school, 24.0%, higher than 5.3% of the middle and high school. It showed a significant difference(p<.001). OHP or epidiascopes were used at the primary school, 36.4%, significantly higher than the middle and high school(p<.001). In addition, computer was used at the primary school, 21.5%, higher than the middle and high school(p<.05). Problems of obesity education data included a lack of textbooks and programs and a short of educational media. However it didnt show a significant difference in schools or in regions. Counseling activities for obesity showed a significant difference in schools(p<.01) and in regions(p<.001). When parents with obese students were in counseling, those in their 20s used home correspondence and those in their 30s and 40s used phone call(p<.01). The rate of equipment to measure obesity was higher at the middle and high school than the primary school, showing a significant difference(p<.001). Therefore, regular health education curriculums for school nurses should be systematically created to promote student health. Furthermore, it needs to make standard textbooks for health education by grades as well as by levels and to develop various educational programs and educational media.

• Korean Journal of Microbiology
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• v.36 no.2
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• pp.79-83
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• 2000

Activated sludge samples were collected from a municipal sewage treatment plant and used for enrichment of microbial consortia with aniline as the sole carbon and nitrogen source. Threc aniline-degrading bacteria were obtained lrom microbial consortia and an isolate which has excellent aniline degradability was selected for this study. The isolate was Gram-negative, and identified and designated as Delfha sp. JK-2 on the basis of various physiological and biochemical tests. 10 mM aniline was completely degraded within 24 hours after inoculation of the culture. Ammonium ion was liberated in the medium transiently during the incubation and disappeared when aniline was completely degraded. Addition of glucose as a supplementary source to aniline minimal media showed significant decrease in aniline degradat~on rate for the strain Effective degradation of aniline was achieved by the addition of 0.5% nitrate as a nitrogen source, and resulted in approximately 80% higher aniline degradation compared to the absence of nitrate. Phylogenetic analysis based on 16s [DNA sequence revealed that the strain was closely related to De@ia acidovorans, with 96% overall similarity. The 16s [DNA sequence of JK-2 was also found to be closely related to those of six other clonal types, including Acidovoru, Aquaspirillum. Xylophilus, Variovorm, and Rhodofernr.

• Phonetics and Speech Sciences
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• v.12 no.3
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• pp.1-14
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• 2020

Previous studies have confirmed that /o/ and /u/ in Seoul Korean are undergoing a merger in the F1/F2 space, especially for female speakers. As a substitute parameter for formants, it is reported that female speakers use phonation (H1-H2) differences to distinguish /o/ from /u/. This study aimed to explore whether H1-H2 values are being used as perceptual cues for /o/-/u/. A perception test was conducted with 35 college students using /o/ and /u/ spoken by 41 females, which overlap considerably in the vowel space. An acoustic analysis of 182 stimuli was also conducted to see if there is any correspondence between production and perception. The identification rate was 89% on average, 86% for /o/, and 91% for /u/. The results confirmed that when /o/ and /u/ cannot be distinguished in the F1/F2 space because they are too close, H1-H2 differences contribute significantly to the separation of the two vowels. However, in perception, this was not the case. H1-H2 values were not significantly involved in the identification process, and the formants (especially F2) were still dominant cues. The study also showed that even though H1-H2 differences are apparent in females' production, males do not use H1-H2 in their production, and both females and males do not use H1-H2 in their perception. It is presumed that H1-H2 has not yet been developed as a perceptual cue for /o/ and /u/.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.78-93
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• 2013

The purpose of this study is to analyze college students' perception of national natural heritages, including natural monumentsand scenic sites, in comparison with the similar concepts of national parks and eco-landscape preservation areas, to suggest managerial implications to enhance competitiveness. The first objective of this study is to measure their attitude toward traveling each type of natural heritage and to rate the relative importance of the four types of heritages in terms of preservation. Natural monuments were perceived as the most strongly preserved type, while scenic sites were perceived as the least strongly preserved type. The second objective is to conduct a correspondence analysis to match the concepts of four types of natural heritages with 10 tourist attractions representing the types. It was found that college students have difficulty appropriately identifying the types of 10 tourist attractions. In addition, multi-dimensional scaling (MDS) was implemented to identify the similarities and differences of the four types of natural heritages and to produce a positioning map matching the four types of natural heritages with the six attributes representing each type as a tourist attraction. Natural monuments were perceived very differently from scenic sites and not very differently from eco-landscape preservation areas. There were a few associations between the four types of natural heritages and the six tourism attributes, implying that little effort is made to promote and position each type of natural heritage in terms of tourism. In conclusion, a public awareness program is required to enhance the brand image of natural monuments and scenic sites in comparison to national parks and eco-landscape preservation areas. In addition, local residents who live near the natural heritages should be bolstered to play a managerial role as supporters and contents providers for sustainability.

• Journal of agricultural medicine and community health
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• v.36 no.2
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• pp.113-119
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• 2011

The aims of this study were to survey, evaluate the accuracy of personal immunization record of vaccination card, and to establish the applicability of personal immunization record for presuming population based immunization rate and evaluation method. In 2005, a population-based survey of 12-35 months old children was carried out in Nonsan, Korea. We conducted household survey and provider check using questionnaire and checklist to obtain data on immunization status for children. Total 11 vaccinations were checked in vaccination card such as BCG, hepatitis b, polio, chickenpox vaccine. For estimating accuracy of immunization status and dates of immunization, we estimated correspondence rate between data from personal vaccination card and data from medical records and immunization registry data. Accuracy of the child's vaccination card by type of National Immunization Program vaccine in whole medical institutions were from 41.8% to 83.2%. Accuracy for the date of vaccination of vaccination card in National Immunization Programme vaccine were from 55.3% to 89.7%. In spite of this study limitations, this study verified the validity of vaccination record of vaccination card substantially, but suggests more efforts to reassure the validity of vaccination card.