• Journal of Educational Research in Mathematics
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• v.16 no.3
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• pp.221-249
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• 2006

The object of this study is to understand the characteristics of mathematical knowledge that elementary 5th graders have regarding the statistical variation concept and the changes after taking lessons. This study includes a pretest to examine the characteristics of mathematical knowledge that elementary 5th graders have regarding the statistical variation concept. And It was followed by a lesson on statistical variation concept to be able to correct error which was revealed by the inspection, and to improve good points. It turned out that after five lessons on the statistical variation concept, the insufficient aspects were properly improved, and as for the points they already understand, they came to understand better than before. They came to consider the statical variation concept instead of the frequency, preponderance, average, stable traits for the optimum value. Also, through the lesson on drawing tables and graphs, they came to better understand them, analyzing correctly the exercises in which tables and graphs were combined. When comparing data sets whose general distributions and extents were similar, students came up with the right answers in a stable way by considering averages combining statistical variation too. Since they tended to interpret a situation with their own subjective views adding conditions, teachers need to examine the proper situation and conditions prior to the lessons on the statistical variation concept.

• Korean journal of applied entomology
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• v.28 no.2
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• pp.61-68
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• 1989

To investigate the possibility of the BPH control by systematic application of insecticides, biological effects of buprofezin and isoprothiolane upon the BPH population was evaluated in the laboratory and pot. Both chemicals did not affect the developmental period of the nymphal stage with the applied dosages. When the buprofezin treated instar nymph was developed to the adult, adult's longevity was fairly reduced and such an effect of buprofezin was greater upon the younger instar nymphs. Residual effect of buprofezin was about 30 days in the pot. And it could suppress the BPH population when the younger instar nymphs were dominant age group in the population at the time of treatment. Isoprothiolane was also more effective for the suppression of the BPH population when the younger instar nymphs were dominant at the time of treatment. And it was expected that by buprofezin treatment in July the control effect of isoprothiolane against the BPH population could be maximized when it was treated to control the rice neck blast in late July or early August, because buprofezin could induce the biased population age distribution in which younger instar nymphs were main group at the time of isoprothiolane treatment.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.69-75
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• 2011

This study was conducted to investigate the variation of cone, seed and germination characteristics among populations and among individuals within populations of Picea jezoensis(Siebold & Zuccarini) Carriere distributed in Korea. Cone collected from 25 trees in two natural populations(Mt. Jiri and Mt. Dokyu) and their thirteen cone and seed characteristics as well as three germination behaviors were analyzed. Statistical analysis showed significant differences among populations and among individuals within populations in 9 traits except for seed breadth, seed weight, index of seed wing and mean germination time. Generally, morphological variation of cone and seed wings from Mt. Jiri population has smaller and longer than those of Mt. Dokyu population. Percentage of sound seeds and Tetrazolium test from Mt. Jiri population showed 1.79 and 1.87 higher values than Mt. Dokyu population, respectively. The maximum germination percentage was obtained at the optimum temperature of $20^{\circ}C$ and in this case, mean germination time and germination rate showed 7.5 days and 2.9 ea./day, respectively. In seed germination behaviors, percentage(40.7%) and rate(0.90 ea./day) of germination in Mt. Jiri population were more higher and faster than those of Mt. Dokyu population(17.7%, 0.37 ea./day). According to correlation analysis, P. jezoensis populations with small restricted distribution may have been reduced because seed qualities were correlated with increased levels of inbreeding and disproportion flowering.

• Land and Housing Review
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• v.2 no.1
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• pp.19-33
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• 2011

This study considers sustainability in new town development projects in the Tokyo metropolitan area. Since the mid-1980's the purpose of new Town projects in Japan changed from encouraging residential development to sustaining self-sufficiency within multi-functional cities. Nevertheless simultaneous increases in elderly population and declines in general population became the new town's key issue. Is this trend a general phenomenon in Tokyo? Has the multi-functional city policy failed? What policies can encourage new town self-sufficiency? Judging from this research, the new towns of Tokyo are relatively young areas with low aging rates and low rates of population decrease. Nevertheless, in view of the multi-functional city plan, levels of self-sufficiency and social-mix in most new towns are inadequate. Considering these, this research recommends new town plans be required to consider surrounding industries and the accessibility form CBD to encourage self-sufficiency. Moreover, The social mix plan encouraging residential diversity is important to the sustainability of the new town.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.2
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• pp.139-147
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• 2009

The gravity data collected and reserved in Korea is seriously biased in its distribution. That is, only the west-southern part of the peninsula including Chungcheong and Jeonla area has dense distribution while only a part is covered in Gyoungsang area. Especially, the low density of the gravity data in mountainous area basically limits the accuracy of the gravimetric geoid in Korea. As one of the solution to overcome the problem, an airborne gravity survey were conducted from Dec. 2008 $\sim$ Jan. 2009. In this study, free-air gravity anomaly derived from the airborne gravity data which has consistent quality are presented. The data processing for the airborne gravity is composed of several corrections of errors such as errors from gravity measurement, errors from flight dynamics, errors from GPS, and errors from time synchronization. We presented detailed explanations on the data processing with the final cross-over results. The free-air anomaly from airborne gravity finally shows the cross-over accuracy of 2.21mGal which reflects the precision of each track is 1.56mGal. It is expected that the result from this study will play a role as input data in precision geoid determination with ground and ship-borne gravity data after appropriate fusion process.

• Journal of Life Science
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• v.32 no.9
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• pp.690-697
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• 2022

This study was conducted to analyze genome of red sea cucumber and to use it as basic data for the development of genetic markers for red sea cucumber. Microsatellite marker analysis of Ulleungdo_normal and Ulleungdo_native red sea cucumbers revealed that dinucleotide simple sequence repeats (SSRs) had the highest ratio, at 81.3~81.4%, and the number of the detected SSRs tended to decrease as the number of repeating sequence units in SSRs increased. In general, microsatellites with between 5 and 10 iterations were most common. As the size of the SSR repeating sequence units increased, the SSR iterations gradually decreased. The di-, tri-, and tetra-nucleotides in SSRs were detected in the highest numbers as (AT)₅, (AAT)₅, and (AAAT)₅, respectively. (CG) and (CCG) had very low frequencies compared to the numbers of other repeating SSR units. The numbers of di-and tri-nucleotide repeats were up to 35 and 32, respectively, and then increased discontinuously up to 44 and 43 repeats, respectively. Tetra-, penta-, and hexa-nucleotides in SSRs occurred in numbers up to 25, 21 and 14, respectively. This analysis of red sea cucumber indicated that it maintains its own repetition sequence and repetition number; therefore, we suggest that using it as basic data for molecular marker will be possible in future research.

• Smart Media Journal
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• v.13 no.5
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• pp.33-44
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• 2024

Chungbuk has various regional characteristics in terms of population composition by region, industrial facilities, and distribution of emergency medical institutions. However, there are no studies yet that have analyzed regional characteristic factors related to the occurrence characteristics of cardiac arrest patients. Therefore, this study provided basic data to establish a response system for OHCA patients suitable for the characteristics of the Chungcheongbuk-do region by analyzing the characteristics of OHCA patients and the transfer status of 119 paramedics in Chungcheongbuk-do. This study is a retrospective study that analyzed 1,188 cardiac arrest patients transferred by ambulance based on raw data from the survey on acute cardiac arrest in Chungbuk (2020). There are a total of 11 emergency medical institutions in Chungbuk-do, which are concentrated in city-level areas, so the transfer time of patients to hospitals in county-level areas was delayed. In the county-level area, the frequency of dispatch of special paramedics was relatively small, and the frequency of administration of cardiac arrest drugs to help resuscitate cardiac arrest patients was also low. In conclusion, efforts should be made to improve accessibility of emergency medical services (deployment of emergency vehicles in marginal areas, proper placement of emergency medical institutions, etc.), to promote prevention of traumatic cardiac arrest patients, and to expand the scope of work to strengthen the first aid expertise of paramedics.

• Journal of Korean Society of Disaster and Security
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• v.17 no.1
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• pp.1-8
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• 2024

In Korea, mountainous areas cover 60% of the land, leading to increased factors such as concentrated heavy rainfall and typhoons, which can result in debris flow and landslide. Despite the high risk of disasters like landslides and debris flow, there has been a tendency in most regions to focus more on post-damage recovery rather than preventing damage. Therefore, in this study, precise topographic data was constructed by conducting on-site surveys and drone measurements in areas where debris flow actually occurred, to analyze the risk zones for such events. The numerical analysis program RAMMS model was utilized to perform debris flow analysis on the areas prone to debris flow, and the actual distribution of debris flow was compared and analyzed to evaluate the applicability of the model. As a result, the debris flow generation area calculated by the RAMMS model was found to be 18% larger than the actual area, and the travel distance was estimated to be 10% smaller. However, the simulated shape of debris flow generation and the path of movement calculated by the model closely resembled the actual data. In the future, we aim to conduct additional research, including model verification suitable for domestic conditions and the selection of areas for damage prediction through debris flow analysis in unmeasured watersheds.

• Journal of agricultural medicine and community health
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• v.25 no.2
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• pp.231-244
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• 2000

Classification and research trends were studied to analyze a total of 240 original articles that have been published in 34 volumes of The Korean Journal of Rural Medicine from 1976 to 1999. The results were as follows: 1. A total of 337 articles were published. Among them, 240(71.2%) articles were classified as original articles. This number has been increasing significantly over the years as the number of the articles was 13 in the 1970s, 73 in the 1980s, and 154 in the 1990s. 2. There were 10 authors in the original articles and 55(22.9%) of them were written by 3 of them. There were five research institutions involved in the articles, and 106(44.2%) of the articles were done by one research group. 3. In the original articles. 24(10.0%) were noted to be done using research funds, and only 6(2.5%) were written in English. 4. In the view of the research styles of the original articles, 115(47.9%) used analytical study, 92(38.3%) used technical study, 21(9.2%) used experimental study, and 6(2.5%) used case reports. In the 1970s, 13(100.0%) articles used technical study, and in the 1980s, 47(64.4%) used technical studies and 19(26.0%) used analytical studies. However, in the 1990s, 96(62.8%) articles used analytical studies and 32(20.9%) used technical studies. The statistical methods most commonly used in the articles were technical statistics, the ${\chi}^2$-test, and the t-test respectively. 5. On the classification into three different research fields, 105(43.8%) articles were classified as health management, 96(40.0%) as disease epidemiology, and 39(16.3%) as rural environment and rural occupational disorders. In the 1970s, 12 (92.3 %) of the articles were on disease epidemiology and 1(7.7%) on health management were published. In the 1980s, 33(45.2%) articles on disease epidemiology, 29(39.7%) on health control, and 11(15.1%) on rural environment and rural occupational disorders were recorded. In the 1990s, however, 75(48.7%) articles were on health control, 51(33.1%) on disease control, and 28(18.2%) on the rural environment and rural occupational disorders. 6. According to the research subjects in each research field, the 39 articles in rural environment and rural occupational disorders were composed of 8(20.5%) articles on pesticide intoxication, 7(17,9%) on farmer's diseases, 7(17.9%) on vinyl-house diseases, and 6(15.4%) on accidents. From a total of 96 articles in disease epidemiology 56(58.3%) articles were on parasites, 16(16.7%) on non-infectious diseases, 12(12.5) on infectious diseases. From 105 articles in health control 25(23.8%) articles were on medical care utilization patterns, 18(17.1%) on the health care delivery system, and 13(12.4%) on maternal and child health. In the analysis of the 10 most prevalent subjects dealt in the above articles, 6(46.2%) articles were on parasites and 4(30.8%) on non-infectious diseases were recorded in the 1970s. In the 1980s, 28(38.4%) were on parasites. 9(12.3%) on the health care system, 7(9.6%) on medical care utilization patterns, 5(6.8%) on maternal and child health, and 4(5.5%) were on pesticide intoxication. In the 1990s, 22(14.3%) articles were on parasites. 18(11.7%) on medical care utilization patterns, 16(10.4%) on senile health, 14(9.1%) on the health care system, 10(6.5%) on infectious diseases, arid 10(6.5%) were on non-infectious diseases. In conclusion, the research activity on rural health has been strengthened in this country because the original articles in The Korean Journal of Rural Medicine have significantly increased in the past 24 years. In the 1970s and 1980s, research on disease epidemiology was most prevalent, but in the 1990s papers on health care were most popular. In addition, the articles on parasites were most frequently published in the 1970s, 1980s, and 1990s, showing that parasitic problem was the main theme in those eras. However, in the 1990s, it was evident that the articles on parasites were decreasing and articles on the subject of medical care utilization patterns and senile health increased. Hereafter it was expected that research on health care would be more common in rural health in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.2
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• pp.89-98
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• 2008

The purpose of this study was to suggest the basic data for establishment of wildflower pastures. The experimental design includes two treatments: Native wildflower pasture (NWP, Kentucky bluegrass + native wildflower 8 species) and Introduced wildflower pasture (IWP, Kentucky bluegass + introduced wildflower 24 species). The field trials were carried out on the experimental pastures plots at Chungnam National University throughout from Sep. 2006 to Dec. 2007. The results obtained are as fellows: In terms of the flower color in the wildflower pastures, the IWP was found more various than the NWP. But such problems as seasonal distribution and continuity were raised and moreover the time of flowering depended mainly upon the spring season. Even though the flower color in the NWP did not show up its variousness, seasonal distribution and continuity were found comparatively satisfactory. To perennially maintain the botanical composition, the variousness of wildflower species are found important after examining locally the beginning rearing and flowering characteristics of wildflowers as well as the basic turfgrass. Moreover, when the wildflower pastures was constructed in autumn, since most of the introduced wildflower were annuals, it maintained various botanical composition before wintering, but after wintering the botanical composition were found simplified due to the winter tolerance. The NWP did not show any problems in the winter tolerance but it could not make the botanical composition diversified. Accordingly, to maintain the wildflower pasture for many years, diversifying wildflower species based upon perennials including annuals seems to be good.