• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.287-295
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• 2010

Dust samples have been collected from streets, schools, subway stations and households in Daegu metropolitan city. Samples were sieved through a 100 ${\mu}m$ mesh and the concentration of 14 elements have been determined using by ICP after acid extraction. Results showed that Ca, Fe, K, Mg, Mn, Na and V were influenced by natural sources while Cd, Cr, Cu, Ni, Pb and Zn were influenced by anthropogenic sources. The measured values were remarkably higher in components from natural sources than in components from anthropogenic sources. In particular, school dust had higher levels of Ca and Pb and subway station dust had higher levels of Cu and Zn. The percentage composition of chemicals from subway stations, households, and schools were remarkably higher in components from anthropogenic sources than that from streets. It is well recognized that anthropogenic sources were affected by indoor dust. Results of pollution index of hazardous heavy metals indicated that schools, households, and subway stations were more contaminated than streets and urban areas typically had higher pollution index than rural areas. The correlation analysis among trace elements seem to suggest that there were correlations between components of soil/road dust resuspension, and components of waste incineration and fuel combustion.

• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.343-354
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• 2018

In this study, the first experience of the whole research process of a novice scientist (student A) who participated in the Undergraduate Research Program (URP) was analyzed. The data were collected through observation, interviews, and document analysis with the cultural historical activity theory being used as a theoretical lens. At the beginning of novice's research, the mentor guided him in setting a research goal and provided mediating artifacts. Student A formed a research team based on the vertical relationship without a shared mental model. Two major contradictions occurred and they were the sources of changes of student A's activity system. The first contradiction was between the mentor's educational philosophy and the mentee's educational needs, which was resolved in a way that student A asked and used the mentor's network to obtain his needs about task-specific details. The second contradiction arose because the team members wanted horizontal relationship while student A wanted to stick to the vertical relationship. After student A accepted the opinions of the team members, they cooperatively changed the division of labor in the activity system. Student A decided to become a scientist and not a physics teacher, even if his major is physics education after finishing his URP research process. His URP experience also created and expanded his network in the academic field, and his negative attitude toward collaboration changed positively. Through the analysis of the structure and changes in the activity system of URP research, implications for instructional method and support system of the apprenticeship can be obtained.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.694-702
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• 2017

In the case of an elevated railway station, structure borne noise and vibration due to structural limitations allow the load and vibration from railway vehicles to be directly transmitted to the station structure, resulting in an increase in the number of civil complaints from customers and staff of the station. The floating slab track system, which is well known as one of the solutions for reducing the noise and vibration from elevated railway stations, usually contains rubber mounts or rubber pads under the railway slab which act as a damper. These types of device have the disadvantage that is difficult to predetermine the exact stiffness and damping ratio under the nonlinear loads resulting from train services. In this study, an isolator with a friction type of wedge is introduced, which can be applied to floating slab track systems and to be designed with precisely the required stiffness. Furthermore, a comparative analysis of the stiffness between the designed and experimental values is carried out, while the damping ratio, which is closely related to the friction wedge blocks, is deduced according to the train load condition. The performance tests of the isolator were conducted in accordance with the DIN 45673-7 standard which includes both static and dynamic load tests. The load conditions for the performance tests are designed to conform to the DIN standard related to the weight of the train and rail track, in order to perform vertical and horizontal load tests, so as to ensure the secure structural safety of the railway. Also, by checking the change aspect of the friction coefficients of the friction elements according to the loading rate, the vibration reduction performance of the friction type isolator with variable loading rate conditions is examined.

• Korean Journal of Social Welfare Studies
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• v.41 no.3
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• pp.349-378
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• 2010

The Life-Course perspective is a theoretical orientation that views the life-course as the age structure embedded in social institutions and history and understands the life-course of individual and group in the contextual perspective. The life-course perspective studies were developed in Germany and North America. They study social and historical effects and the effect of institutions and the state on the life-course, the pathway of the work career and differences of labour outcomes, and the inequality that is developed in the life-course. In Korea, the life-course perspective studies were tried in various fields and cumulated. However, it didn't established as a theoretical orientation. For applying the life-course perspective to connect the individual life-course with social and historical event, I describe the historical location of individuals born between 1930 and 1979 and analyse the change of their transitions to adulthood exploratorily. On results, the extension of education made the structural change of their life-course, and in young cohort the timing of leaving school, entering workforce, marriage and childbirth was delayed and transitions were made in narrower spread. It means the standardization of the life-course as appears in modern society. The 1970s birth cohort has the differenciated life-course pattern, however I cannot verify that change because of the right censoring.

• School Mathematics
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• v.18 no.2
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• pp.277-300
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• 2016

In school mathematics, the definition and concept of a differentiation has been dealt with as a formula. Because of this reason, the learners' fundamental knowledge of the concept is insufficient, and furthermore the learners are familiar with solving routine, typical problems than doing non-routine, unfamiliar problems. Preceding studies have been more focused on dealing with the issues of learner's fallacy, textbook construction, teaching methodology rather than conducting the more concrete and efficient research through experiment-based lessons. Considering that most studies have been conducted in such a way so far, this study was to create a lesson plan including teaching resources to guide the understanding of differential coefficients and derivatives. Particularly, on the basis of the theory of Historical Genetic Process Principle, this study was to accomplish the its goal while utilizing a technological device such as GeoGebra. The experiment-based lessons were done and analyzed with 68 first graders in S high school located in G city, using Posttest Only Control Group Design. The methods of the examination consisted of 'learning comprehension' and 'learning satisfaction' using 'SPSS 21.0 Ver' to analyze students' post examination. Ultimately, this study was to suggest teaching methods to increase the understanding of the definition of differentials.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.15-20
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• 2006

In this study the flow characteristics of smoke and heat on a bank type platform of the underground subway station are studied numerically by considering two different emergency operation modes. Effects of the natural flow through the tunnel and the stair ways are considered in the numerical simulations by using the measured velocities presented in Part I as the boundary condition. Distributions of heat, smoke, visible range and toxic gas on the platform are analysed for different smoke extraction flowrates corresponding to the two different emergency operation modes. The numerical results show that the extraction flowrate affects the smoke control performance significantly by improving the smoke removal performance as the extraction flowrate is increased.

• Journal of Korea Water Resources Association
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• v.56 no.10
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• pp.667-678
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• 2023

In this study, quasi-3D inundation flow simulations were conducted for a simplified subway station configuration. The effects of variations in rainwater inflow locations and discharge were investigated, analyzing the resulting inundation flow patterns and flood risk. The inundation simulation results calculated the incipient velocities for slipping and toppling accidents to assess pedestrian safety. The results indicated that velocities exceeding the incipient velocity for slipping accidents mainly occurred on the flooded staircase. Meanwhile, velocities surpassing the incipient toppling accidents were observed around the staircase and the corridor near the staircase leading to B2F. This observation is consistent with the results from the specific force distribution analysis. To provide detailed flood risk assessments, the Flood Hazard Degree (FD) was applied with four levels of criteria, along with the Flood Intensity Factor (FIF). The results demonstrated that FD identified a broader area at risk of flood-induced consequences compared to FIF. When comparing the different inundation risk assessment methods, the specific force method tended to overestimate the risk area, whereas FIF tended to underestimate it. Furthermore, among all assessment methods, the influence of rainwater discharge was found to have a more dominant effect on flood risk assessment compared to the number of rainwater inflow locations. Additionally, the direction of inundation flow influenced the assessed risk, with collision-induced flow patterns leading to higher flood risk than those with identical flow directions.

• Fire Science and Engineering
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• v.25 no.4
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• pp.8-21
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• 2011

This study surveyed historical records on outbreak and features of forest fires during Chosun Dynasty's 518 years in being and analyzed the Annals of the Chosun Dynasty; The Diaries of the Royal Secretariat, archives from Records of the Border Defense Council, The Compilation of Ministry Proposals, Posthumous Records of King Cholchong etc. Forest fires were most prevalent and extreme during King Hyunjong (14 cases) and King Sunjo (13 cases) due to strong wind, and the biggest-ever forest fire broke out in the fourth year of King Soonjo (1804) in the east coast of Korea in Kangwon province. The fire had resulted in 61 fatalities and 2,600 destroyed houses. Forest fire in the east coast of Korea, Kangwon province, in the $13^{th}$ year of King Hyeonjong (1672) is recorded to have caused the highest number of deaths, 65people. The most frequent cause of forest fires during Chosun Dynasty was unidentified (42 cases), followed by accidental fire (10 cases), arson or lightning (3 cases), fire during hunting (2 cases), play with fire by children, destruction of patty fields and dry fields by fire and house fire (1 case respectively). By region, 56 % of forest fires erupted in the east coast (39 cases) and this was followed by the west sea (9 cases), Seoul and central region (8 cases) and the southern part of Korea (7 cases). By season, spring was found to be most vulnerable to forest fire as it accounted for 73 % of the total amounting to 46 cases. Behind were summer (11 cases), winter (6 cases) and autumn (0 case). Specifically, most forest fire broke out on April and May, which is the same as today. Archives and literature indicate that the person who involved in forest fire by accidental as well as arson had to be punished by banishment, expulsion from government office and public hanging. Also, officials in charge of the region that suffered forest fire were subject to reprimand. In conclusion, risk and gravity of forest fires were evident during the Chosun Dynasty as specified in historical archives and share many similarities with today's forest fires in terms of the duration and regional patterns.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2002.11a
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• pp.76-76
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• 2002

본 실험은 Piezo-미세조작기(PrimeTech Ltd., Japan)를 사용하여 마우스 핵이식 후 재구축배를 CZB와 KSOM 두가지 배양액을 사용하여 체외배양성적을 비교 검토하였다. MII의 미수정란은 성숙한 4~5주령 B6D2Fl에 hCG 주사 후 14시간째에 과적 방법을 통해 난관의 팽대부로 부터 회수하였고, metaphase II chromosome-spindle complex와 최소량의 세포질을 내경이 10$\mu\textrm{m}$인 피펫으로 흡입하여 탈핵하였다. 핵이식에 사용된 난구세포(8-l0$\mu\textrm{m}$)는 3시간동안 12% PVP 에처리 하여 piezo-미세조작기를 이용하여 세포질에 세포의 핵을 직접 미세주입 하였다. 핵이식 후 생존한 재구축배는 2시간동안 배양한 후 10mM SrC1$_2$와 5$\mu\textrm{g}$/$m\ell$의 cytochalasin B가 첨가된 $Ca^{2＋}$-free CZB에서 6시간 활성화 처리하였다, 활성화 처리 후 위전핵이 관찰된 재구축란을 CZB 와 KSOM 배지에서 배양하면서 발달률을 비교하였고, 상실배 및 배반포배로 발달한 재구축배를 day 3 대리모에 이식하였다. 표 1에서 보는 바와 같이 재구축배의 2-cell로의 발달률에 있어서 KSOM이 CZB에 비하여 유의적으로 높게 나타났으며(P<0.05), 또한 4-cell과 상실배/배반 포배로의 발달률에 있어서도 KSOM이 CZB에 비하여 유의적으로 높은 발달률을 나타내었다(P<0.01). 또한 KSOM 배지에서 배양된 상실배/배반포배를 대리모에 이식한 경우에 11.5 d.p.c에 생존한 태아가 관찰되었다. 이상의 결과로 핵이식 재구축배의 활성화 처리 후의 발생에는 KSOM 배지가 CZB 배지에 비하여 유효함을 확인 할 수 있었다.그와 같은 배양 기술을 이용하여 외래유전자를 도입한 일련의 결과에 관하여 보고 하고자한다., 이것은 세포내 유전자가 transfection되지 않은 세포도 neo selection에서 선발된다는 것을 제시하고 있다. 따라서 체세포를 이용한 형질전환동물 생산을 위해서는 세포내 유전자 도입과 선발 과정에서 나타난 colony에 대하여 보다 엄격한 screen을 하는 것이 필요한 것으로 생각된다.로 우점하였다. 여름철 식물플랑크톤 대발생에 영향은 수온과 직산염이 중요하였으나, 부유물질 크게 기여하지 못하였다.애를 확인하고 지도 관점을 파악하는 것을 포함한다. 그러나 본 논문은 역사발생적 수학 학습-지도 원리의 실제적인 적용에 관하여는 기초적인 연구에 지나지 않기 때문에, 역사발생적 원리를 학교수학에 실제적으로 적용하기 위해서는 각각의 내용에 대한 철저한 역사적 분석을 바탕으로 하는 후속 연구가 필요하다./TEX>구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to look into the origin of the letter designs in t

• The Korean Journal of Archival Studies
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• no.46
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• pp.189-231
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• 2015

This study is for establishing an appraisal methodology to ensure the accountability of the parliament and to documentation the contemporary historical events related to the National Assembly. It is impossible to documentation comprehensively the activities of the National Assembly through the records schedule of the National Assembly, the current the disposal guidelines of the National Assembly. In particular, this is designed focusing on four affiliated organizations such as the National Assembly Secretariat, so there is a fundamental limit to documentation the outputs of various external agencies and areas where have relationships with the National Assembly. Therefore, it is hard to documentation comprehensively the various issues and historical events occurring in the National Assembly under the current appraisal system. In this situation, this study presents the appraisal methodology, the institutional functional analysis to ensure the accountability of the institution as a first step. However, only with the institutional functional analysis methodology, it is difficult to organize collectively the contemporary historical events or social events ongoing in relation to the fundamental functions of the National Assembly. For this reason, the subject oriented documentation methodology is designed that is the appraisal methodology of selecting the records related to the contemporary social phenomena and historical events according to the functional areas of the National Assembly derived from the institutional functional analysis methodology. Thereby, it is designed that the model of the documentation strategy applicable to the National Assembly in reality.