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A Comparative Study on the Secondary School Mathematics Education of South and North Korea (남북한 중등학교 수학교육의 통합방안 모색)

  • Woo, Jeong-Ho;Park, Moon-Whan
    • Journal of Educational Research in Mathematics
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    • v.12 no.1
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    • pp.49-70
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    • 2002
  • There have recently been increasing exchanges between South and North Korea in many areas of society, involving politics, economics, culture, education. In response to these developments, research activities are more strongly demanded in each of these areas to help prepare for the final unification of the two parts of the nation. In the area of mathematics education, scholars have started to conduct comparative studies of mathematics education in South and North Korea. As a response to the growing demand of the time, in this thesis we compared the secondary mathematics education in South Korea with that in North Korea. To begin with, we examined the background of education, in North Korea, particularly predominant ideological, epistemological and teaching theoretical aspects of education in North Korea. Thereafter, we compared the mathematics curriculum of South Korea with that of North Korea. On the basis of these examinations, we compared the secondary school mathematics textbooks of South and North Korea, and we attempted to suggest a guideline for researches preparing for the unification of the mathematics curriculum of South and North Korea. As a communist society, North Korea awards the socialist ideology the supreme rank and treats all school subjects as instrumental tools that are subordinated to the dominant communist ideology. On the other hand, under the socialist ideology North Korea also emphasizes the achievement of the objective of socialist economic development by expanding the production of material wealth. As such, mathematics in North Korea is seen as a tool subject for training skilled technical hands and fostering science and technology, hence promoting the socialist material production and economic development. Hence, the mathematics education of North Korea adopts a so-called "awakening teaching method," and emphasizes the approaches that combine intuition with logical explanation using materials related with the ideology or actual life. These basic viewpoints of North Korea on mathematics education are different from those of South Korea, which emphasize the problem-solving ability and acquisition of academic mathematical knowledge, and which focus on organizing as well as discovering knowledge of learners' own accord. In comparison of the secondary school mathematics textbooks used in South and North Korea, we looked through external forms, contents, quantity of each area of school mathematics, viewpoints of teaching, and term. We have identified similarities in algebra area and differences in geometry area especially in teaching sequence and approaching method. Many differences are also found in mathematical terms. Especially, it is found that North Korea uses mathematical terms in Hangul more actively than South Korea. We examined the specific topics that are treated in both South and North Korea, "outer-center & inner-center of triangle" and "mathematical induction", and identified such differences more concretely. Through this comparison, it was found that the concrete heterogeneity in the textbooks largely derive from the differences in the basic ideological viewpoints between South and North Korea. On the basis of the above findings, we attempted to make some suggestions for the researches preparing for the unification in the area of secondary mathematics education.

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A Study on the Deformation Behavior of the Segmental Grid Retaining Wall Using Scaled Model Tests (조립식 격자 옹벽의 변형거동에 관한 모형실험 연구)

  • Bae, Woo-Seok;Kwon, Young-Cheul;Kim, Jong-Woo
    • Tunnel and Underground Space
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    • v.17 no.5
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    • pp.350-359
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    • 2007
  • Most large cut slopes of open pit mines, roadways, and railways are steeply inclined and composed with rocks that do not contain soils. However, these rock slopes suffer both weathering and fragmentation. In the case of steep slopes, falling rock and collapse of a slope may often occur due to surface erosion. Cast-in place concrete and rubble work are the most widely used earth structure-based pressure supports that act as restraints against the collapse of the rock slope. In order to overcome the shortcomings of conventional retaining walls, a segmental grid retaining wall is being used with connects precasted segments to construct the wall. In this study, laboratory model test was conducted to estimate deformation behavior of segmental grid retaining wall with configuration of rear strecher, height and inclination of the wall. In order to examine the behavior characteristics of a segmental grid retaining wall, this research analyzes the aspects of spacial displacement through relative displacement according to change in the inclination of the wall. Also, the walls behavior according to the formation and status of the rear stretcher which serves the role of transferring the load from the header and the stretcher which make up the wall, the displacement of backfill materials in the wall, and the location of the maximum load were surveyed and the characteristics of displacement in the segmental grid retaining wall were observed. The test results of the segmental grid retaining wall showed that there was a sudden increase in failure load according to the decrease in the wall's height and the size of the in was greatly decreased. Furthermore, it revealed that with identical inclination and height, the structure of the rear stitcher did not greatly affect the starting point or size of maximum horizontal displacement, but rather had a stronger effect on the inclination of the wall.

A Study on the Removal of Heavy Metals from Groundwater Using Permeable Reactive Barriers Based on Nano FeS (나노 FeS를 이용한 투과성반응벽체의 중금속 오염 지하수 처리에 관한 연구)

  • Jung, Gwan-Ju;Choi, Sang-Il;Lee, Jai-Young
    • Journal of Soil and Groundwater Environment
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    • v.14 no.6
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    • pp.19-28
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    • 2009
  • The acid mine drainage (AMD) and landfill leachates released into the subsurface environment can result in serious environmental problems like soil and groundwater contamination. The AMD and the leachates of landfill were known to contain many heavy metals. In this study, the author assessed the reactivity and ability of the FeS coated-ALC for the removal of contaminants (As, Cd, Cu, Pb, Ni, Zn, Al) in AMD and leachates in landfill. The synthetic nano-FeS and Autoclaved Lightweight Concrete (ALC) were used as reactive materials in the permeable reactive barriers(PRBs). The result of batch test indicated that synthetic nano-FeS can remove 99% of heavy metals for the 1hr of reaction time except for As and Ni(about 90%). However, the 80% of As and Ni was removed in column 1(FeS coated-ALC). The column 2(Ore FeS) removed more than 99% of heavy metals. The pH of the column 1 was increased from 3.51 to 6.39~6.50, and the pH with column 2 was increased from 3.51 to 9.20. As the result of this study, the author can surmise that the synthetic nano-FeS coated ALC will use as a very good reactive material of the PRBs to treat the contaminated groundwater with AMD and leachate of landfill.

Fabrication of lightweight geopolymer based on the IGCC slag (IGCC 용융 슬래그를 이용한 경량 지오폴리머 제조)

  • Park, Soo-bin;Kim, Kang-duk;Kang, Seung-gu
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.6
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    • pp.319-326
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    • 2017
  • In this study, a lightweight geopolymer was prepared using by slag discharged from IGCC (Integrated Gasification Combined Cycle) power plant and its physical properties, the density and compressive strength, were analyzed as a function of the concentration of alkali activators, W/S ratio and aging times. Also the possibility of applying it to lightweight materials by adding Si sludge as a foaming agent to the geopolymerg was investigated. In particular, a complex composition of alkali activator and a pre-curing process were applied to improve the strength properties of lightweight geopolymers. While the compressive strength of the lightweight geopolymer using a single activator was 9.5 MPa, the specimen made with a complex composition of alkali activator had compressive strength of 2~5 times higher. In addition, the lightweight geopolymer with pre-curing process showed a compressive strength value of 18~48 % higher than that of specimen made with no precuring process. In this study, by using a complex activator and a pre-curing process. the maximum compressive strength of lightweight geopolymer was obtained as 40 MPa (The specimen was aged for 3 days and had density of $1.83g/cm^3$), which is comparable to cement concrete. By analyzing the crystal phase and microstructure of geopolymers obtained in this study using by XRD and SEM, respectively, it was confirmed that the flower-bud-like zeolite crystal was homogeneously distributed on the surface of the C-S-H gel (sodium silicate hydrate gel) in the geopolymer.

A Study on the knowledge and attitude of AIDS In college students (일 대학 학생들의 AIDS에 대한 지식, 태도의 관한 연구)

  • Choi, Gil-Soon;Chae, Min-Jeong
    • The Korean Journal of Emergency Medical Services
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    • v.13 no.2
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    • pp.73-86
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    • 2009
  • Purpose : This study is a descriptive correlation study to offer the basic materials for developing the preventive program of continuously increasing AIDS in the young people by examining the knowledge and attitude of AIDS in college students. Methods : The period of data collection was from May 1 to 15, 2009, 300 freshman, sophomore and junior students who understood the purpose of the research and agreed to participate in the questionnaire were randomly sampled, structured questionnaire was distributed to them and their responses were collected. Instruments used for this study included those used by Kim and Lee and revised and complemented by this researcher to measure the knowledge of AIDS and those by Yun and Lee revised and complemented by the researcher to measure the attitude of AIDS. For data analysis, it measured technical statistics, t-test, ANOVA, and Pearson's correlation coefficient using SPSS/PC 12.0. Results : The results of this study are summarized as follows. 1. The whole knowledge of AIDS the subjects had scored 58.9 and their average attitude scored $3.78(1{\pm}25)$. 2. In the degree of knowledge of AIDS depending on general characteristics and health-related characteristics of the subjects, it was found that the students at the department of emergency medical showed higher knowledge(t=3.638, p=.001) and positive attitude of AIDS(t=3.330, p=.001) compared to students at other majors. 3. In the degree of knowledge of AIDS depending on AIDS-related education, subjects who had experienced AIDS education(t=1.973, p=.050), those with the experience of theory education(F=4.057, p=.008), those who felt the necessity of AIDS education(t=4.588, p=.000), and those who were willing to take part in AIDS education(t=2.898, p=.004) showed higher know1edge of AIDS. In the attitude of AIDS, subjects with theory-oriented AIDS education(F=3.012, p=.032), those who felt the necessity of AIDS education(t=2.445, p=.015), and those who were willing to take part in AIDS education(t=2.379, p=.018) showed positive attitude of AIDS education. 4. As the knowledge of AIDS the subjects was higher(r=.329, p=.000), they showed more positive attitude of AIDS and it meant that there was positive correlations. Conclusion : Consequently, systematic, concrete and continuous education of AIDS suitable to the requirements of college students is needed to induce changes of their knowledge and attitude of AIDS and for this, AIDS education program which can be used properly by the developmental stages of college students who belong to late adolescence should be developed in the field of school and if possible, curriculum of sex education including AIDS education should be established in all departments of college.

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The Study on Education and Training Raise the Effectiveness for University Hospital Employee. (대학병원종사자의 교육훈련 유효성 제고를 위한 연구)

  • Kim, Young-Bae
    • Korea Journal of Hospital Management
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    • v.12 no.4
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    • pp.96-118
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    • 2007
  • This study were tried to suggest basic materials for making education and training plan, and members of organization were researched about thinking of education and training effectiveness and perceptible level. The subjects of this study were 762 hospital employee selected from ten of university hospitals in Seoul, Incheon, and Kyung Gi which are doing an education and training, and conducted a self-completion questionnaire. As a result of study and plan for raising the effectiveness were indicated following statements. Firstly, according to the general specific, training effectiveness was appeared similar. So, it requires suitable alternatives to make educational programs. Secondly, according to analysis of education and training necessity, achieving a goal for education and training have difference. it needs to be scientific analysis about necessity of education and training. Thirdly, when contents of education and training program are satisfied to educatee and fit for them, thinking of education and training effectiveness is higher. Therefore, establishing the goal of education training is concrete, realistic, and measurable for increasing learning motivation. Next to, thinking of education and training effectiveness is higher, when education and training person in charge taught to educatee very well, and they were satisfied about teaching. Consequently, they who nourishment of education and training person in charge within company have to improve their ability. And then, when educatee fit for teaching technique and satisfied about it, thinking of education and training effectiveness is higher. So, education and training were tried to find many of technique for fitting the desire of educatee. Sixth, the more education and training environment is satisfactory, the more educatee have high thinking of education and training effectiveness. CEO in hospitals have to think about many-sided solution for employee. Seventh, the more education and training have correct achieving organizational goal, the more educatee have high thinking of education and training effectiveness. Accordingly, hospital management should make up for education and training system. Then, thinking of education and training effectiveness is higher, when education and training measure an effect, and reflect to personnel management and assessment of an employee's performance. It should be the feedback for using information which is planning education and training. In conclusion, when result of measurement of education and training reflect to make a education and training plan, thinking of education and training effectiveness is higher, and result of measurement of education and training should reflect to make a education and training plan.

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Comparision Between Noise Levels of Hospital Wards and the Nurses Efforts for Noise Management in Selected General Hospital (종합병원 병동별 간호사실의 소음정도와 간호사실들의 소음인지도 및 소음관리노력 비교)

  • Jung, Hyun-Wook
    • Korean Journal of Occupational Health Nursing
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    • v.10 no.2
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    • pp.174-182
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    • 2001
  • This study was performed to find out the differences between noise levels of hospital wards and the nurses efforts for noise management in some general hospitals. The hospital wards selected were the intensive care unit(ICU), the emergency room(ER), the nursery room(NR), the internal medicine(IM), the general surgery(GS) among the 5 general hospitals located in Seoul. The data were collected from August 3 to September 13, 1999 through questionnaire survey and noise measurement in each nursing station of hospital wards. Data analysis was done by SPSS 8.0 package among the 305 questionnaires and 24 hours monitored noise levels. Frequency, Chi-square and ANOVA test were used. The study results were as belows: 1. The noise level measured by 24 hours monitoring survey were exceeded on the standard limit in all the hospital wards. Data also showed that noise levels were significantly different in each ward among the three shifts working duties. 2. The subjects were all female nurses. They were mostly working in the ICU ward(28.9%). They were 26~30 years old (43.9%), junior college graduates(57.0%), working for 1~5 years(55.1%) as staff-nurse(85.6%). There were no significant differences between hospital wards and general characteristics of nurses. 3. The noise levels perceived by nurses were regarded as 'Highly noisy'(56.4%), especially during the 11:30 and 15:30 (30.2%) o'clock. Data also showed that noise education was not ever given to nurses(89.9%). Nurses also responded that they hardly put an effort to reduce noise level(54.8%). However, there were significant differences between wards and noisy working time, experience of noise education and level of effort for noise reduction. 4. Nurses also perceived the ventilator alarm and EKG-alarm as the most disturbing sounds in the ICU, human voice and telephone ringing in the ER, human voice and EKG-alarming in the NR, human voices and telephone ringing in IM and GS both wards respectively in order. There were significant differences between hospital wards and noise making factors. 5. Nurses were shown that they regarded highly 'Sound reduction of the human voice', 'Careful handling on medical instruments', and 'Immediate appliances on alarming materials' as the practical method for noise management. There were significant differences between hospital wards and behavioral practical efforts for noise management. According to that results, the statistical differences were shown in the 24 hour monitored noise levels in each ward. Also, nurses perceived the noise severity differently and they approached variously on the practical efforts for noise reduction in each ward. Thus, author thinks that concrete and systematic endeavor will be necessary for noise reduction and management in hospitals for better working and healing environment for both of patients and staffs.

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Experimental evaluation of fire protection measures for the segment joint of an immersed tunnel (침매터널 세그먼트조인트의 내화 대책에 대한 실험적 평가)

  • Choi, Soon-Wook;Chang, Soo-Ho;Kim, Heung-Youl;Jo, Bong-Hyun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.13 no.3
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    • pp.177-197
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    • 2011
  • In this study, a series of fire experiments under $HC_{inc}$ and ISO834 (duration of 4 hour) fire scenarios were carried out for three different types of fire protection measures for the segment joint to evaluate their applicabilities to an immersed tunnel. The experimental results revealed that an expansion joint installed to allow relative movements between concrete element ends in an segment joint is the most vulnerable to a severe fire. For the fire protection measure where the originally designed steel plates at an expansion joint arc replaced by fire-resistant boards, the experiments showed that they cannot achieve good fireproofing performance under both $HC_{inc}$ fire scenario and ISO834 (4 hour) fire scenarios since the installation of fire-resistant boards results in the reduction of the sprayed fire insulation thickness. On the other hand, the application of modified bent steel plates replacing the original steel plates was proved to be very successful in fireproofing of the expansion joint due to more sprayed materials filled in bent steel plate than in the original design concept as well as higher adhesion between the steel plate and the sprayed fire insulation layer.

A numerical study of pillar reinforcing effect in underground cavern underneath existing structures (지하공간하부 지하저류공동에서의 필라 보강효과에 관한 수치해석적 연구)

  • Seo, Hyung-Joon;Lee, Kang-Hyun;Han, Shin-In;Lee, In-Mo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.5
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    • pp.453-467
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    • 2012
  • Usage of underground space is increasing at metropolitan city. More than 90% of flood damages have occurred at downtown of metropolitan cities. In order to prevent and/or minimize the flood-induced damage, an underground rainwater detention cavern was proposed to be built underneath existing structures. As for underground caverns to be built for flood control, multi-caverns will be mostly adopted rather than one giant cavern because of stability problem. Because of the stress concentration occurring in the pillars between two adjacent caverns, the pillar-stability is the Achilles' heel in multi-caverns. So, a new pillar-reinforcing technology was proposed in this paper for securing the pillar-stability. In the new pillar-reinforcing technology, reinforced materials which are composed of a steel bar and PC strands are used by applying pressurized grouting, and then, by applying the pre-stress to the PC strands and anchor body. Therefore, this new technology has an advantage of utilizing most of the strength that the in-situ ground can exert, and not much relying on the pre-cast concrete structure. The main effect of the pressurized grouting is the increase of the ground strength and more importantly the decrease of stress concentration in the pillar; that of the pre-stress is the increase of the ground strength due to the increase of the internal pressure. In this paper, ground reinforcing effects were verified the stress change in pillar is obtained by numerical analysis at each construction stage. From these results, the effects of pressurized grouting and pre-stress are verified.

Direction of Laws and Policies for the Regulation of Internet Personal Broadcasting (국내외 인터넷 개인방송 규제현황 및 규제 방향성 제언)

  • Lim, Han Sol;Jung, Chang Won
    • The Journal of the Korea Contents Association
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    • v.20 no.2
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    • pp.248-264
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    • 2020
  • This study aims to analyze the social and legal status of Internet personal broadcasting in Korea and propose the direction of personal broadcasting regulation based on overseas regulatory laws and the media characteristics of Internet broadcasting. The influence of Internet personal broadcasting has increasing, and social and legal problems such as pornography and fake news have also growing. In the absence of legal regulations on personal broadcasting on the Internet, academia is also discussing relevant legislation and policies at a general level of analysis. In addition, the current study argues that new legislative research is needed to respond to the rapidly changing media environment and to cope with the newly introduced Internet broadcasting content and platforms. The findings suggest that freedom of expression is a significant value, yet obscene materials for minors should be thoroughly regulated, and that internet personal broadcasting should be regulated to the minimum extent through self-regulation guidelines through cooperation between councils and related agencies or businesses. The significance of the current study indicates that it proposed the practical and concrete laws for the improvement of the quality of Internet personal broadcasting content, the establishment of new broadcasting policies for fair and diverse content development, and the efficient and fair regulation of personal broadcasting content.