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The Present Situation and Science High School Teachers' Perception about Field Application of the GLOBE Program in Korea (국내 글로브 프로그램 운영 현황 및 지도교사들의 인식)

  • Lee, Moon-Won;Kim, Hwa-Sung;Ludman, Allan
    • Journal of the Korean earth science society
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    • v.31 no.1
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    • pp.63-70
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    • 2010
  • The purpose of this study was to investigate the application of GLOBE program in Korea and its perception displayed by the Science High school Teachers. The interview using a questionnaire with 12 science high school teachers in Korea was conducted. It was attempted to find a problem occurring during the practical application for getting a basic data for the development of Korean GLOBE program. The results of this study are as follows: (1) The level of GLOBE program was for upper grade levelsin elementary school and middle school. The program may not be suitable for the Science High School students in Korea. (2) To successfully apply the GLOBE program in Korea, study levels and research subjects in the program must be further developed in terms of quality and areas. Suggestions for the possibility of adopting and operating the program in Korea are made as follows: (1) To effectively manage the GLOBE school sites, there has to be a headquarter system in place and operation under, say, the Korean Earth Science Society. (2) To ensure the program's identity and goals, it is to set up a center for the Korea GLOBE program with a financial support system established.

Dismantling Simulation of Nuclear Reactor Using Partial Mesh Cutting Method for 3D Model (3D 형상 모델의 부분 절단 기법을 이용한 원자로 해체 시뮬레이션)

  • Lee, Wan-Bok;Hao, Wen-Yuan;Kyung, Byung-Pyo;Ryu, Seuc-Ho
    • Journal of Digital Convergence
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    • v.13 no.4
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    • pp.303-310
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    • 2015
  • Game technologies are now applied in various engineering areas such as the simulation of surgical operation or the implementation of a cyber model house. One of the essential and important technology in these applications is cutting of the 3D polygon model in real time. Real-time cutting technology is an essential technology needed to implement the simulation of a building demolition or a car assembly for training or educational purpose. Previous cutting method using the conventional BSP-Tree structure has some limitations in that they divide the whole world including the 3D model and its environment, only into two parts with respect to an infinite plane. In this paper, we show a technique cutting the 3D model in a finite extent in order to solve this problem. Specifically, we restricted the cut surface in a finite rectangular area and constructed the mesh for the divided surface. To show the usefulness of our partial cutting technique, an example of the dismantling process simulation of a nuclear reactor polygon model was illustrated.

Pile Load Transition and Ground Behaviour due to Development of Tunnel Volume Loss under Grouped pile in Sand (사질토 지반에서 터널체적손실 증가에 따른 군말뚝의 하중변이와 지반거동)

  • Oh, Dong Wook;Lee, Yong Joo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.2
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    • pp.485-495
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    • 2017
  • A development of underground space is very useful solution to slove problem occurred from ground surface enlargement in urban areas due to the growth of population, tunnelling is the most popular way and widely used. Researches regarding tunneling-induced pile-soil interactive behaviour have been conducted by many researchers. A study on pile axial force distribution due to tunnelling through laboratory model test, however, is being rarely carried out. In this study, therefore, authors investigate ground behaviour due to tunnelling below grouped pile subjected vertical load as well as pile axial force distribution. A concept of volume loss is used to express tunnel excavation, which is normally applied to 1~2% for tunnelling in soft ground. In this study, however, 10% of that applied to investigate failure mechanism. As a result of laboratory model test, a decrease of pile axial force occurs at 1.5% of volume loss, settlement of grouped pile is 1.2~4.7 times greater than the adjacent ground surface one. Ground deformations at 1.5% of volume loss are measured using Close Range Photogrammetry and compared with results from numerical analysis.

Pollutants Removal Efficiency of Rainfall-runoff from Dense Highland Field Areas in Multistage Sedimentation Basins - Focused on Jaun Area in Upstream Watershed of Lake Soyang - (고랭지 밭 밀집지역 다단계 침사지의 강우-유출 오염물질 제거 효율 - 소양호 상류의 자운지구를 중심으로 -)

  • Cho, Jae Heon
    • Journal of Environmental Impact Assessment
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    • v.27 no.2
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    • pp.170-180
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    • 2018
  • Highland fields are concentrated in the Jaun area of Hongcheong-gun, a large amount of sediments are discharged from the highland fields. The sediment runoff affect the turbidity and water quality of the Soyang Lake, furthermore adversely affect water supply source of the capital region. There are several kinds of BMPs(Best management practices) to decrease the sedimentrunoff from the highland fields. Although construction cost of multistage sedimentation basins is very high, there is no actual survey data for the removal efficiency of suspended sediments and water quality in our country. In this study, stormwaterinflow and outflow of the multistage sedimentation basins were surveyed, and the removal efficiency of nonpoint source pollutants were analyzed. The stormwater survey results fortwo rainfall events show thatremoval efficiencies of SS, BOD and TP loads in the multistage sedimentation basins are 35%~62%, 24%~55%, 35%~58%, respectively. Although the measured efficiencies of the basins were lower than the theoretical efficiency, the proper operation and management can improve the removal rate of the basins. Turbid water problem in the upper parts of the Soyang River can be managed effectively through the additional installation of multistage sedimentation basins.

Reconstruction of the Extremities with the Dorsalis Pedis Free Flap (족 배 유리 피부판을 이용한 사지 재건술)

  • Lee, Jun-Mo;Kim, Moon-Kyu
    • Archives of Reconstructive Microsurgery
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    • v.8 no.1
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    • pp.77-83
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    • 1999
  • The skin on the dorsum of the foot is a source of the reliable thin and sensory cutaneous free tissue transplantation with or without tendon, bone and joint. A composite flap with attached vascularized tendon grafts for the combined loss of skin and tendon on the dorsum of the hand and foot offers an immediate one stage solution to this problem. The flap provides a very durable innervated tissue cover for the heel of the foot and the dorsum of the hand and an osteocutaneous transfer combined with the second metatarsal. The major dorsalis pedis artery is constant in size, but the first dorsal metatarsal artery is variable in size and location. The dorsal surface of the foot receives sensory innervation through the superficial peroneal nerve and the first web through the deep peroneal nerve. Authors had performed 5 dorsalis pedis free flap transplantation in the foot and hand at Department of Orthopedic Surgery, Chonbuk National University Hospital from August 1993 through August 1997 and followed up for the period of between 19 and 67 months until March 1999. The results were as follows 1. 5 cases dorsalis pedis free flap transfer to the foot(4 cases) and the hand(1 case) were performed and the recipient was foot dorsum and heel 2 cases each and hand dorsum 1 case. 2 All of 5 cases(100%) were survived from free flap transfer and recipient artery was dorsalis pedis artery(2 cases), anterior tibial artery(1 case), posterior tibial artery(1 case) and ulnar artery(1 case) and recipient veins were 2 in number except in the hand. 3. Long term follow up of the exterior and maceration was good and sensory recovery was poor 4. Donor site was covered with full thickness skin graft obtained from one or both inguinal areas at postoperative 3rd week and skin graft was taken good and no morbidity was showed.

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Agent-Based Collaborative Design System and Case-Based Conflict Resolution (원격공동설계 시스템 구축을 위한 에이전트 기반 접근 및 사례기반 의사충돌 해결)

  • 이경호;이규열
    • Journal of Information Technology Application
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    • v.1
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    • pp.99-127
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    • 1999
  • Under the concept of global economy, the enterprises are assigning design and production environments around the world in different areas. A serious problem of information exchange emerges as companies use traditional hardware and very distinct softwares appropriate to their field of expertise. To overcome the decreased productivity due to the interruption of information, the concept of simultaneous engineering and concurrent design becomes very significant. In this article, an agent-based ship design system is developed in order to support a cooperation in distributed ship design environments. Above all, the conflicts that occur in the middle of knowledge sharing in the system must be resolved. An approach to do this is the case-based conflict resolution strategy formulated to resolve current conflict on the basis of previous resolved similar cases in agent-based collaborative design system environments. To do this conflict cases that occur in initial ship design stage are extracted. On the basis of the extracted cases, case-base is constructed. In addition conflict resolution handler located in the facilitator is developed to treat conflict problems effectively by reasoning of the case-base and thus presenting an appropriate solution. The validation of developed case-based conflict resolution strategy is evaluated by applying to collaborative design process in initial ship design stage, especially the machinery outfitting design, the preliminary design, the hullform design, and the structural design. Through the help of the cooperation of the design agents, the facilitator, the conflict resolution handler, and the case-based system, a designer can be supported effectively in his/her decision-making based on the previous cases resolved similarly.

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A Survey to Investigate Teachers' Perception of Core Competencies and Affective Aspects in Mathematics (수학의 핵심역량과 정의적 측면에 대한 교사들의 인식 조사 연구)

  • Kim, Dong-Won;Park, Kyung-Mee;Park, Mimi
    • School Mathematics
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    • v.17 no.1
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    • pp.99-118
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    • 2015
  • The purpose of this study is to investigate teachers' perception of core competencies and affective aspects in mathematics. For this purpose, a nationwide survey was conducted. The survey questionnaire consists of three core competencies including problem solving, reasoning and communication, and two affective aspects including good human nature and attitudes. The survey results were further analyzed based on school level, teaching experience, location of schools, and types of high schools. As a result, four findings were identified. First, elementary school teachers tend to put more emphasis on core competencies and affective aspects than secondary school teachers do. Second, in elementary school level, longer teaching experience is correlated with more positive perception of core competencies and affective aspects. However, there was an opposite tendency in secondary school level. Third, teachers working at schools in metropolitan cities tend to emphasize core competencies and affective aspects more than those at schools located in mid-sized cities and rural areas. Fourth, the school types in high school didn't seem to affect the teachers' perception on core competencies and affective aspects.

Eye Movements in Understanding Combinatorial Problems (순열 조합 이해 과제에서의 안구 운동 추적 연구)

  • Choi, In Yong;Cho, Han Hyuk
    • Journal of Educational Research in Mathematics
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    • v.26 no.4
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    • pp.635-662
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    • 2016
  • Combinatorics, the basis of probabilistic thinking, is an important area of mathematics and closely linked with other subjects such as informatics and STEAM areas. But combinatorics is one of the most difficult units in school mathematics for leaning and teaching. This study, using the designed combinatorial models and executable expression, aims to analyzes the eye movement of graduate students when they translate the written combinatorial problems to the corresponding executable expression, and examines not only the understanding process of the written combinatorial sentences but also the degree of difficulties depending on the combinatorial semantic structures. The result of the study shows that there are two types of solving process the participants take when they solve the problems : one is to choose the right executable expression by comparing the sentence and the executable expression frequently. The other approach is to find the corresponding executable expression after they derive the suitable mental model by translating the combinatorial sentence. We found the cognitive processing patterns of the participants how they pay attention to words and numbers related to the essential informations hidden in the sentence. Also we found that the student's eyes rest upon the essential combinatorial sentences and executable expressions longer and they perform the complicated cognitive handling process such as comparing the written sentence with executable expressions when they try the problems whose meaning structure is rarely used in the school mathematics. The data of eye movement provide meaningful information for analyzing the cognitive process related to the solving process of the participants.

Usefulness of Full-thickness Skin Graft from Anterolateral Chest wall in the Reconstruction of Facial Defects (안면부 재건에서 전외측 흉벽을 공여부로 하는 전층 피부이식술의 유용성)

  • Yoo, Won-Jae;Lim, So-Young;Pyon, Jai-Kyong;Mun, Goo-Hyun;Bang, Sa-Ik;Oh, Kap-Sung
    • Archives of Plastic Surgery
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    • v.37 no.5
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    • pp.589-594
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    • 2010
  • Purpose: Full thickness skin grafts are useful in the reconstruction of facial skin defects when primary closure is not feasible. Although the supraclavicular area has been considered as the choice of donor site for large facial skin defect, many patients are reluctant to get a neck scar and some patients do not have enough skin to cover the defect owing to the same insult occurred to the neck such as burn accident. We present several cases of reconstruction of facial skin defects by freehand full-thickness skin graft from anterolateral chest wall resulting aesthetically acceptable outcome with lesser donor site morbidity. Methods: Retrospective review was performed from March, 2007 to September, 2009. 15 patients were treated by this method. Mean age was 31.5 years. The ethiology was congenital melanocytic nevus in 7 cases, capillary malformation in 5 cases and burn scar contracture in 3 cases. Mean area of lesion was measured to 67.3 cm2 preoperatively. The lesion was removed beneath the subcutaneous fatty tissue layer. The graft was not trimmed to be thin except defatting procedure. For the larger size of defect, two pieces of grafts were harvested from both anterolateral chest wall in separation and combined by suture. Results: The mean follow up period was 9.7 months. All the grafts survived without any problem except small necrotic areas in 4 cases, which healed spontaneously under conventional dressings in 6 weeks postoperatively. Color match was relatively excellent. There were 2 cases of hyperpigmentation immediately, but all of them disappeared in a few months. Conclusion: In cases of large facial skin defects, the anterolateral chest wall may be a good alternative choice of full-thickness skin graft.

Current status and the changing pattern of the prevalence of clonorchiasis in the inhabitants in Sanchong-gun, Kyongsangnam-do, Korea (경상남도 산청군 주민의 간흡충 감염 상황변화)

  • 이종수;이원자
    • Parasites, Hosts and Diseases
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    • v.31 no.3
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    • pp.207-214
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    • 1993
  • This study was conducted to evaluate the current endemicity and the transition mode of the Clonorchis infection in Sanchong-gun Kyongsangnam-do. The areas of investigation, villages and schools surveyed, method and techniques used in this study were the same as in 1984. The egg positive rate of clonorchiasis in the general population of Sanchong-gun was 37.6% out of 837 exanuned persons. In the schoolchildren. the rate was 9.7% out of 145 persons examined. In the Intensity of the infEction among the cases. the mean EPG (Egg Per gram of feces) in the inhabitants and schoolchildren were 3, 310 (male 4, 221, female 1, 978) and 711 tamale 620. female 8331, respectively. Of the inhabitants with clonorchiasis, the cases of light infection (EPG < 1, 000) and moderate infection (1.000 < EPG < 10, 000) were 93.9%. The proportion with experience of eating raw freshwater-fish was 90.5% among the infecters. Out of 138 Inhabitants examined in both 1984 and 1992, the number of the positives by both examinations was 31 (22.5%), positive to negative conversion was 35 (25.4%), negative to positive conversion was 22(15.9%). The present results reveal that there are no chanties of the e99 Positive rate of clonorchiasis among inhabitants in Sanchong and the eating habit of raw freshwater-fish persists there. In this community, the eating habit Is the most important problem to be solved for control of this endemic diease.

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