• ETRI Journal
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• v.42 no.2
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• pp.247-257
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• 2020

Spatial experiences in route finding, such as the ability of finding low-traffic routes, exert a significant influence on travel time in big cities; therefore, the spatial experiences of seasoned individuals such as taxi drivers in route finding can be useful for improving route-finding algorithms and preventing using routes having considerable traffic. In this regard, a spatial experience-based route-finding algorithm is introduced through ontology in this paper. To this end, different methods of modeling experiences are investigated. Then, a modeling method is chosen for modeling the experiences of drivers for route finding depending on the advantages of ontology, and an ontology based on the taxi drivers' experiences is proposed. This ontology is employed to create an ontology-based route-finding algorithm. The results are compared with those of Google maps in terms of route length and travel time at peak traffic time. According to the results, although the route lengths of route-finding method based on the ontology of drivers' experiences in three cases (from nine cases) are greater than that based on Google maps, the travel times are shorter in most cases, and in some routes, the difference in travel time reaches only 10 minutes.

• Journal of the Korean Geographical Society
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• v.45 no.6
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• pp.820-844
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• 2010

This study investigates the effect of GIS-integrated lessons on spatial thinking abilities and geographical skills using discourse analysis along with a comparative three-case case study method. A series of curricula were designed and implemented in an 8th grade classroom for a semester. The data collected consist of the dialogue transcripts of six consecutive GIS-integrated lessons. The transcripts were analyzed to identify the moves (speech acts) used by each student and to classify discourse content of spatial thinking and geographical skills. Based on three individual case studies, a cross-case study was performed to uncover any relationship between the phenomenon and the contexts. The empirical evidence from discourse analysis demonstrated that students were able to generate appropriate terms representative of spatial thinking and geographical skills although students appeared to possess primarily lower-order spatial abilities, followed by a moderate-level of spatial abilities. Considering that the unit was implemented in a biology class rather than a geography class the result reflected the fact that the student's spatial thinking and geographical skills were attributable to the GIS-integrated lessons. Thus, the results have a great implication for GIS-integrated lessons and geography education as an innovative tool for improving student's spatial thinking and geographical skills.

• Coupled systems mechanics
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• v.7 no.3
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• pp.269-280
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• 2018

Post-earthquake damages investigation in past and recent earthquakes has illustrated that the ground motion spatial variation plays an important role in the structural response of long span bridges. For the structural control of seismic-induced vibrations of cable-stayed bridges, it is extremely important to include the effects of the ground motion spatial variation in the analysis for design of an effective control system. The feasibility and efficiency of different vibration control strategies for the cable-stayed bridge under multiple support excitations have been examined to enhance a structure's ability to withstand earthquake excitations. Comparison of the response due to non-uniform input ground motion with that due to uniform input demonstrates the importance of accounting for spatial variability of excitations. The performance of the optimized designed control systems for uniform input excitations gets worse dramatically over almost all of the evaluation criteria under multiple-support excitations.

• Journal of Korean Association for Spatial Structures
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• v.19 no.2
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• pp.17-25
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• 2019

In this study, we propose a new scheme of nonlinear analysis for Incheon International Airport Terminal-2 which was opened on January of 2018 for the Olympic Winter Games of PyeongChang in South Korea. The terminal was built by a single layered irregular space frame. It has hard problems for nonlinear analysis geometrically, because of a limitation of personal computer's ability by the number of rigid joints in the roof. Therefore we attempt easier approach to be chosen a center part of the roof instead of the whole structure, and to substitute the other boundary parts as springs. The scheme shows some merits for saving memory and calculation time and so on.

• The Journal of Korean Academy of Sensory Integration
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• v.4 no.1
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• pp.47-55
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• 2006

Objective : The purpose of this study was to evaluate the correlation between visual perception ability and activities of daily living(ADL) in the children with spastic diplegia who were treated at developmental disabilities children salutary institute. Method : The subject were consisted of 8 children with spastic diplegia(mean age, 10). The visual perception ability was measured by the Developmental Test of Visual Perception(DTVP) and by the Functional Independence Measure for Children(WeeFIM) to evaluate activities of daily living. Collected data analysis were completed by using correlation analysis. Results : Visual perception ability of children with spastic diplegia is the highest in Position in Space(PS) score, and is the lowest in Visual-Motor coordination(VM) score. Average visual perception performance of children with spastic diplegia is the highest in SR(Spatial relationship) score, and is the lowest in VM score. In activities of daily living, eating component were significantly correlated with Visual-Motor coordination. Conclusions : Therefore, accurate evaluation of visual perception ability and visual perception training for children with spastic diplegia will be important to improve patient's activities of daily living skill.

• Journal of the Korean association of regional geographers
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• v.14 no.3
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• pp.269-278
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• 2008

This research analyzed the effect of lessons with the GIS application as an alternative scheme of teaching and learning of geography in elementary school. Two classes in the third grade at Y elementary school in Andong were selected to conduct lessons on 'The Landscape of My Hometown' from March 6 through June 30, 2006. In the experimental class, the lessons were conducted with the GIS application; while, in a comparative class, the lessons were carried with usual teaching and learning method. To find out the effect of lessons with the GIS application, differences of spatial cognition of students were figured out between groups, and before and after lessons. The difference between the spatial concept development stages and materials on the textbook discouraged students to pursue their learning as well as made them hard to achieve the goals of lessons. The GIS application had been suggested as an alternative teaching and learning method to overcome the difference; however, it has been hard to find any empirical research to verify the effect of the lessons with GIS application in elementary school. The ability of spatial cognition of the third graders at an elementary school was very low as the result of that curricula in the first and second grades dealt with sketch maps as teaching and learning media. The map learning of third grader on the transitional stage would play the critical role to develop the spatial cognition ability in the future. The field study contributing to developing spatial cognition ability would not be conducted at school. It was required to have the alternative learning schemes such as lessons with GIS application. The lessons with GIS application verified effect of GIS application as the alternative method. The GIS application helped students to recognize landmarks, directions and distance effectively as well as reduced the spatial cognition difference among individuals and/or groups.

• Journal of the Korean School Mathematics Society
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• v.13 no.2
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• pp.303-322
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• 2010

The purpose of this study was to analyze the effects of using the geometric manipulative for the development of spatial sense and thus to find out a better mathematics teaching and learning method that could help develop students' spatial senses. The two fifth grade classes were randomly chosen as an experimental group (31 students) and a control group (32 students), respectively. This study implemented nonequivalent control group pretest-posttest design of quasi-experimental design. The test instrument used in this study was a spatial sense test. The pretest and posttest were implemented with the same instrument. In addition, their classes were observed and videotaped, and the data and their study activities were analyzed. In conclusion, first, the geometric manipulative-aided activities contributes to developing students' spatial senses and their two sub-factors involves perceptual consistency and perception of spatial relationship. Second, the activities of grasping the components of solid figures, sketches and development figures by using the geometric manipulative contribute to boost students' perceptual consistencies and their perceptions of spatial relationship.

• Spatial Information Research
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• v.8 no.1
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• pp.155-170
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• 2000

When we use R-Tree,a spatial index, to find objects matches some predicate, it often leads to an incorrect result of perform filtering step only with MBR. And , each candidates need to be inspected to conform if it really satisfies with given query, so called, 'refinement step'. In refinement step. we should perform disk I/O and expansive spatial operations which is the cause of increasing retrieval costs. Therefore, to minimize the number of candidate after filtering step, two-phase filtering methods were studied, but there was many problems such as inefficiency of filtering,maintenance of additional informations and reconstruction of data resulted from the loss of original information. So , in this paper, I propose an Extended R-Tree which provides ability to retrieve spatial objects only with some simple logical operations using Grid Table, truth table strong the information about the existence of spatial objects, in second filtering step. Consequently , this Extended R-Tree using Grid Filter has low cost of operation for filtering because of efficient second filtering step, and better filtering efficiency caused by high quality of approximation.

• Animal cells and systems
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• v.7 no.4
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• pp.303-307
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• 2003

The aim of this study is to investigate whether alcohol alters learning and memory processes pertaining to emotional and spatial factors using the active avoidance and T-maze task in zebrafish. In the active avoidance task, zebrafish were trained to escape from one compartment to another to avoid electric shocks (unconditioned stimulus) following a conditioned light signal. Acquisition of active avoidance task appeared to be normal in zebrafish that were treated with 1% alcohol for 30 min for 17 days until the end of the behavioral test, and retention ability of learned behavior, tested 2 days later, was the same as control group. In the T-maze task, the time to find a reservoir was compared. While the latency was similar during the 1 st training session between control and alcohol-treated zebrafish, it was significantly longer in alcohol-treated zebrafish during retention test 24 h later. Furthermore, when alcohol was treated 30 min after 2nd session without prior treatment, zebrafish demonstrated similar retention ability compared to control. These results suggest that chronic alcohol treatment alters spatial learning of zebrafish, but not emotional learning.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.4
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• pp.559-566
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• 2013

PURPOSE: The present study examines how feedback respiratory exercise affects gait performance of stroke patients. METHODS: Forty stroke patients were randomly divided into an experiment group and a control group. For the former group, patients went through a half-hour of training therapy and a half-hour of feedback respiratory device exercise. For the latter group, patients went through 30 minutes of training therapy and a half-hour of motomed exercise. All participants had five training sessions each week for four weeks. For measurement, a GAITRite system was used to examine spatial parameters, and functional ambulation performance before and after the training. RESULT: In terms of spatial parameters, double support ratio, stance phase increased significantly in the experiment group after the walking exercise(p<.05). FAP rose more significantly in the experiment group than in the control group(p<.05). In comparison of two exercise groups, double support ratio, Stance phase, gait velocity, FAP was significant difference(p<.05). CONCLUSION: The experiment results showed that feedback respiratory exercise is effective in enhancing gait performance.