• Journal of the Korean association of regional geographers
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• v.5 no.1
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• pp.163-185
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• 1999

The purpose of this study is to develop the model of constructivist multimedia-assisted instruction(CMAI) and to analyze the effect of it in the secondary school geography. The main results are as follows : (1) The conceptual model of CMAI can be defined as an instruction aiming at making a person who has self-directed learning ability through constructivism and multimedia. The procedural model of CMAI based on PIDA instructional strategy is divided into four stages : prediction & explanation, inquiry activity, discussion & fixation, application & synthesis stage. (2) CMAI is typed by offline CMAI and online CMAI. that is, O/WCMAI(online CMAI by web-based courseware). Offline CMAI is subdivided into P/TCMAI(offline CMAI by presentation-based courseware) and C/RCMAI(offline CMAI by cd-rom based courseware) according to authoring tool and function. (3) Offline constructivist multimedia course-ware(offline courseware) was developed for 2 periods as the material to analyze the effect of CMAI. Offline courseware is received development level of it. (4) After offline courseware being applied to the class, the effect of it according the types of the CMAI instruction(lecture instruction, whole teaching, individualized learning, cooperative learning) was analyzed. As the result of analyzing the descriptive statistics of the level of learning achievement and instruction response, there isn't big relationship between them. As the result of analyzing the inferential statistics of the level of learning achievement, there wasn't significant difference between the types of CMAI instruction in whole student of the classes and certain students who improved their grades. But as the result of analyzing of the level of instruction response, there was significant difference between lecture instruction and other types of the CMAI instruction(whole teaching, individualized learning, cooperative learning).

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.06a
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• pp.187-187
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• 2009

Opening of fractures induced by shear dilation or normal deformation can be a significant source of fracture permeability change in fractured rock, which is important for the performance assessment of geological repositories for spent nuclear fuel. As the repository generates heat and later cools the fluid-carrying ability of the rocks becomes a dynamic variable during the lifespan of the repository. Heating causes expansion of the rock close to the repository and, at the same time, contraction close to the surface. During the cooling phase of the repository, the opposite takes place. Heating and cooling together with the, virgin stress can induce shear dilation of fractures and deformation zones and change the flow field around the repository. The objectives of this work are to examine the contribution of thermal stress to the shear slip of fracture in mid- and far-field around a KBS-3 type of repository and to investigate the effect of evolution of stress on the rock mass permeability. In the first part of this study, zones of fracture shear slip were examined by conducting a three-dimensional, thermo-mechanical analysis of a spent fuel repository model in the size of 2 km $\times$ 2 km $\times$ 800 m. Stress evolutions of importance for fracture shear slip are: (1) comparatively high horizontal compressive thermal stress at the repository level, (2) generation of vertical tensile thermal stress right above the repository, (3) horizontal tensile stress near the surface, which can induce tensile failure, and generation of shear stresses at the comers of the repository. In the second part of the study, fracture data from Forsmark, Sweden is used to establish fracture network models (DFN). Stress paths obtained from the thermo-mechanical analysis were used as boundary conditions in DFN-DEM (Discrete Element Method) analysis of six DFN models at the repository level. Increases of permeability up to a factor of four were observed during thermal loading history and shear dilation of fractures was not recovered after cooling of the repository. An understanding of the stress path and potential areas of slip induced shear dilation and related permeability changes during the lifetime of a repository for spent nuclear fuel is of utmost importance for analysing long-term safety. The result of this study will assist in identifying critical areas around a repository where fracture shear slip is likely to develop. The presentation also includes a brief introduction to the ongoing site investigation on two candidate sites for geological repository in Sweden.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.96-97
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• 2012

In nitride and oxide film deposition, sputtered metals react with nitrogen or oxygen gas in a vacuum chamber to form metal nitride or oxide films on a substrate. The physical properties of sputtered films (metals, oxides, and nitrides) are strongly influenced by magnetron plasma density during the deposition process. Typical target power densities on the magnetron during the deposition process are ~ (5-30) W/cm2, which gives a relatively low plasma density. The main challenge in reactive sputtering is the ability to generate a stable, arc free discharge at high plasma densities. Arcs occur due to formation of an insulating layer on the target surface caused by the re-deposition effect. One current method of generating an arc free discharge is to use the commercially available Pinnacle Plus+ Pulsed DC plasma generator manufactured by Advanced Energy Inc. This plasma generator uses a positive voltage pulse between negative pulses to attract electrons and discharge the target surface, thus preventing arc formation. However, this method can only generate low density plasma and therefore cannot allow full control of film properties. Also, after long runs ~ (1-3) hours, depends on duty cycle the stability of the reactive process is reduced due to increased probability of arc formation. Between 1995 and 1999, a new way of magnetron sputtering called HIPIMS (highly ionized pulse impulse magnetron sputtering) was developed. The main idea of this approach is to apply short ${\sim}(50-100){\mu}s$ high power pulses with a target power densities during the pulse between ~ (1-3) kW/cm2. These high power pulses generate high-density magnetron plasma that can significantly improve and control film properties. From the beginning, HIPIMS method has been applied to reactive sputtering processes for deposition of conductive and nonconductive films. However, commercially available HIPIMS plasma generators have not been able to create a stable, arc-free discharge in most reactive magnetron sputtering processes. HIPIMS plasma generators have been successfully used in reactive sputtering of nitrides for hard coating applications and for Al2O3 films. But until now there has been no HIPIMS data presented on reactive sputtering in cluster tools for semiconductors and MEMs applications. In this presentation, a new method of generating an arc free discharge for reactive HIPIMS using the new Cyprium plasma generator from Zpulser LLC will be introduced. Data (or evidence) will be presented showing that arc formation in reactive HIPIMS can be controlled without applying a positive voltage pulse between high power pulses. Arc-free reactive HIPIMS processes for sputtering AlN, TiO2, TiN and Si3N4 on the Applied Materials ENDURA 200 mm cluster tool will be presented. A direct comparison of the properties of films sputtered with the Advanced Energy Pinnacle Plus + plasma generator and the Zpulser Cyprium plasma generator will be presented.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.6
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• pp.57-66
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• 2005

In this paper, a new rehabilitation training system was developed to improve equilibrium sense by combining virtual reality technology with a fixed exercise bicycle. The subjects consisted of two groups. A group of young people, was compared against a group of elderly. We measured three different running modes of virtual bicycle system with two successive sets. The parameters measured were running time, velocity, the weight movement, the degree of the deviation from the road, and the variables about the center of pressure. The repeated training, our results showed that the running capability of the elderly improve compared. In addition, it was found out that the ability of postural control and the equilibrium sense was improved with the presentation of the visual feedback information of the distribution of weight. From the results of this experiment, we showed that our newly developed system might be useful in the diagnosis of equilibrium sense or in the improvement of the sense of sight and, somatic, and vestibular sense of the elderly in the field of rehabilitation training.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.85-95
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• 2009

Congestion on expressways is increasing in spite of continuous road construction. In enlargement of expressway capacity to lessen congestion, a long period is needed and in the case of traffic congestion, it would be impossible to avoid long periods of traffic congestion. So, it is necessary to cope with traffic congestion through continuous traffic condition monitoring, analysis of the causes of congestion and the development of alternatives before traffic conditions worsen. A congestion index that can express traffic operating conditions measurably is needed to monitor those conditions. Thus, in this research, a new congestion index, the Traffic Condition Index (TCI), is developed. TCI is able to evaluate roads that have different grades (or design speeds) and to judge traffic condition as good, fair and poor (congested). In addition, TCI has merits in that it can strengthen the function of existing Freeway Traffic Management Systems (FTMS) and can be applied to congestion management easily: TCI calculates congestion intensity and severity using data obtained from existing FTMS. In order to validate TCI, it was applied to the Kyungbu Expressway and the Seohaean Expressway. As a result, TCI shows a good performance in the aspect of applicability and ability of presentation of traffic conditions compared with travel speed and Travel Time Index (TTI).

• The Journal of Internal Korean Medicine
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• v.40 no.5
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• pp.990-998
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• 2019

Introduction: Stroke refers to a sudden brain disease that results in disorders in the anatomy of the brain. The cause is a sudden circulatory disorder of the cerebrovascular system that creates a consciousness disorder and hemiplegia. Despite aggressive treatment after the onset, stroke is a social problem because the patient has difficulty in recovering from sequelae that can include limb movement disorders, language disorders, and emotional disorders. In this study, we describe the effect of traditional Korean medicine treatment on the sequelae in a subacute cerebral infarction patient admitted to a Korean medical hospital. Case presentation: A 67-year-old male patient was diagnosed with cerebral infarction circa 2005, and his condition had not improved. Around March 15, 2018, he experienced the sudden onset of a cerebral infarction in his daily life. This was confirmed by a brain MRI, and he was hospitalized at other hospitals, but he showed no improvement. We conducted a manual muscle test (MMT) to evaluate the patient's exercise and strength. His gait level was measured to evaluate his degree of walking. He was treated with Bojungikgi-tang and acupuncture twice a day. After 34 days of inpatient treatment, the patient's exercise strength improved from Grade 2+~Grade 3 to Grade 3+ determined by the MMT, and his walking ability improved from Gait Level 3 to Gait Level 4. Conclusion: The findings of this study indicate that acupuncture and herbal medicine treatment can help treat patients with hemiplegia due to cerebral infarction.

• Education of Primary School Mathematics
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• v.25 no.2
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• pp.197-211
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• 2022

In this study, we tried to find a way to improve the pedagogical decision-making practices related to the presentation order of 'large number' and 'small number' in problem situations of subtraction of the natural number. For this purpose, the elementary school teachers' perception about problem situations in real-life context of subtraction of natural numbers was investigated, and the collected data were analyzed qualitatively and quantitatively to identify teachers' pedagogical perceptions. As a result of this study, it was confirmed the need for consideration on how to set up a problem situations in real-life context of subtraction so that students can develop their ability to solve various types of problems. To this end, not only in a problem situation of subtraction where you have to think of 'large number' first and 'small number' later, but also about the introduction of problem situations in real-life context of subtraction in which you think about 'small number' first and 'large number' later, which often appears in real-life. You will need to recognize the need. And you should have a pedagogical view on this. The results of this study will be able to contribute to the preparation of pedagogical method that can expand the understanding of various problem situations where subtraction is applied from the lower grades of elementary school.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.34 no.3
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• pp.59-87
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• 2023

The aim of this study is to provide practical instances of implementing picture book reading sessions within school libraries to enhance language proficiency and foster emotional stability among lower-grade multicultural students hailing from foreign backgrounds. The research outlines the design and execution of a picture book reading program tailored for multicultural students, with analysis based on the outcomes of actual classroom implementations. In the course of the study, existing literature pertaining to the use of picture books for enhancing multicultural education and language skills was reviewed. This informed the development of a structured class procedure by extracting core components. Indeed, 43 multicultural students in five classes in the first and second grades of A Elementary School in Gyeonggi-do were given three pilot classes for each class for 20 weeks and a total of 100 picture book reading classes, each with 17 main lessons. This study establishes the positive impact of picture book reading classes on the Korean language comprehension of multicultural students. The results confirm positive improvements in students' ability to understand Korean, as evidenced by enhanced Korean expression and presentation skills, increased library usage, and a positive shift in classroom attitude. The procedure for reading picture books using school libraries proposed in this study was actually conceived and developed in the course of class operation in the school education field, reflecting the changes brought about by the increase of multicultural students and the need to improve the class environment. Through this practical investigation, important insights have been extracted regarding how picture book reading sessions designed for elementary school students from multicultural backgrounds can enhance the classroom environment and elevate learning outcomes.

• Journal of The Korean Association For Science Education
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• v.43 no.4
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• pp.403-414
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• 2023

In this study, we examined the adaptive practices of science teachers in their classrooms and their perspectives on the distinguishing features of these practices within science subjects. Our analysis comprised 339 cases from 128 middle and high school science teachers nationwide, and 199 cases on the characteristics of adaptive practices in science disciplines. The primary findings were as follows: First, the most significant characteristic of adaptive practice in science disciplines pertained to experimental procedures. Within the 'suggestion of additional materials/activities' category, the most frequently cited adaptive practice, teachers incorporated demonstrations to either facilitate student comprehension or enhance motivation. Additionally, 'experimental equipment manipulation or presentation of inquiry skills' emerged as the second most common adaptive practice related to experiments. Notably, over 50% of teacher responses regarding the characteristics of adaptive practices in science pertained to experiment guidance. Second, many adaptive practices involving difficulties experienced by students in learning situations were presented, particularly in areas such as numeracy and literacy. Many cases were related to the basic ability of mathematics used as a tool in science learning and understanding scientific terms in Chinese characters. Third, beyond 'experiment guidance', the characteristic adaptive practices of science subjects were related to 'connections between scientific theory and the real world', 'misconception guidance in science', 'cultivation of scientific thinking', and 'convergence approaches'. Fourth, the cases of adaptive practice presented by the science teachers differed by school level and major; therefore, it is necessary to consider school level or major in future research related to adaptive practice. Fifth, most of the adaptive action items with a small number of cases were adaptive actions executed from a macroscopic perspective, so it is necessary to pay attention to related professionalism. Finally, based on the results of this study, the implications for science education were discussed.

• Journal of the Korean Orthopaedic Association
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• v.54 no.5
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• pp.463-468
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• 2019

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disease that affects the sensory and autonomic nervous system. The patients do not have the ability to sense different sensations, such as pain, which tends to lead to different injuries. In addition, the patients suffer from fluctuations in body temperature due to autonomic involvement. The present case was a five-year-old girl with a neglected distal femur fracture. X-rays taken during the follow-up showed marked callus formation and pseudarthrosis of the distal femur. She had biting injuries of the tongue, auto-amputation of the fingers, some developmental delay and a history of recurrent fever with an unknown origin. The electrodiagnostic study was normal. The quantitative sudomotor axon reflex test revealed markedly reduced postganglionic sudomotor axonal responses at all sites recorded on the left. She was diagnosed with CIPA. As the initial presentation of CIPA involves the musculoskeletal system, orthopedic surgeons should have a high index of suspicion.