• Journal of Biomedical Engineering Research
• /
• v.28 no.5
• /
• pp.590-600
• /
• 2007

We performed experimental studies on the muscle activities in the lower limbs for the different movement patterns on an unstable platform. A training system for postural control using an unstable platform that we previously developed was applied for the experiments. This unstable platform provides 360 degrees of movement allowing for training of posture in various directions and provides simultaneous excitations to visual sensory, somatic sensation and vestibular organs. Compare with the stable platform, keeping body balance on the unstable platform requests more effective sensation from vision, vestibular sense and somatic sense. Especially, the somatosensory inputs from the muscle proprioceptors and muscle force are crucial. To study the muscle activities for the different movement patterns and find the best training method for improving the ability of postural control through training and improving the lower extremity muscular strength, fifteen young healthy participants went through trainings and experiments. The participants were instructed to move the center of pressure following the appointed movement pattern while standing on the unstable platform. The electromyographies of the muscles in the lower limbs were recorded and analyzed in the time and the frequency domain. Our experimental results showed the significant differences in muscle activities for the different movement patterns. Especially, the spectral energy of electromyography signals in muscle for the movement pattern in anterior-posterior direction was significantly higher than those occurred in the other patterns. The muscles in the lower leg, especially tibialis anterior and gastrocnemius were more activated compared to the others for controlling the balance of body on the unstable platform. The experimental results suggest that, through the choice of different movement pattern, the training for lower extremity strength could be performed on specific muscles in different intensity. And, the ability of postural control could be improved by the training for lower extremity strength.

• The Journal of the Korea Contents Association
• /
• v.6 no.8
• /
• pp.38-48
• /
• 2006

Paying attention to the fact that Korean traditional ink and color paintings are different in their use of colors this paper was intended to demonstrate outcomes from the difference in their painting style through specific paintings and thereby categorizing a broad range of oriental paintings into 4 types(Indian ink light color, middle color, deep color, present color) in accordance with the method of using colors, suggest directions that oriental color paintings should move toward in the future in the diversity of modem Paintings. Due to the characteristics of materials, oriental ink paintings, in style, are light in color within lines, which in return makes colors confined to a complimentary role in an overall picture, not having their unique color identity Nevertheless, there are some paintings that use dark colors, which is called moderate saturation. For such dark-color based paintings, colors play a key role, together with the characteristics of materials of color painting, as colors are used to express the most part of a picture. This study, thus, discusses the difference in the use of color depending on style on one hand, and examined the diversity of modem color paintings through specific works on the other hand, since a number of color paintings similar to western Painting in style have been created today. In such diversity, works that are being currently created should contribute to taking over the tradition and further develop oriental colors with modem aesthetic sensitivity. This paper is aimed to help to do harmonious works with traditional and modern paintings by studying and classifying varieties of colors

• The Journal of the Korea Contents Association
• /
• v.18 no.10
• /
• pp.320-334
• /
• 2018

The purpose of this study is to analyze research trends in international development and cooperation on education and to suggest directions for the Korean teachers and teacher education to achieve 'Sustainable Development Goals (SDGs).' The examination of 8 databases resulted in the identification of 2,945 studies, and 6 of these references met the inclusion criteria for systemic review. Major findings revealed that pre- and in-service teachers recognized the necessity of international development education but had a low degree of teacher efficacy. The teachers who participated in ODA education programs have experienced difficulties due to insufficient understanding of local sites and role performance. Then, a couple of studies of mathematics and early childhood education compared the Korean national curriculum and education system with developing countries'. Lastly, it is important to have a sustainable system which promotes all teachers, including retired ones, in global development and cooperation on education. For the successful achievement of SDGs, Korean teachers should develop their expertise, a deep understanding of partner countries, and stable quality education for the underprivileged.

• Korean Journal of Construction Engineering and Management
• /
• v.18 no.6
• /
• pp.89-97
• /
• 2017

The number of Aged Apartment units is expected to increase as time went on. Living standards are getting better and they want a new apartment space as the economy progresses. Therefore, it is necessary to prepare for the increasing remodeling market through the feasibility evaluation method that can be applied to the remodeling project of the apartment house. The purpose of this study is to analyze the social pricing factors affecting the Officially assessed individual House Price for the analysis model of commercial house remodeling. The collected samples were analyzed using multiple regression analysis of 350 prices included in 127 lots. Middle school level, high school level, total number of households, and floor area ratio were extracted. As a result of comparing the Officially assessed individual House Price by applying to the remodeling case, the difference between the existing Officially assessed individual House Price and the improvement Officially assessed individual House Price is different. The accessibility with the subway station is included in the land price, and there is no change in the number of stories and directions because it is customized remodeling. There was a difference in the disclosure price depending on the type of factor extraction by the evaluator in a batch application of the disclosure price factors. The research can be used as a model for future remodeling business feasibility analysis.

• KIPS Transactions on Software and Data Engineering
• /
• v.8 no.12
• /
• pp.491-498
• /
• 2019

Digital twin is a technology that virtualizes physical objects of the real world on a computer. It is used by collecting sensor data through IoT, and using the collected data to connect physical objects and virtual objects in both directions. It has an advantage of minimizing risk by tuning an operation of virtual model through simulation and responding to varying environment by exploiting experiments in advance. Recently, artificial intelligence and machine learning technologies have been attracting attention, so that tendency to virtualize a behavior of physical objects, observe virtual models, and apply various scenarios is increasing. In particular, recognition of each robot's motion is needed to build digital twin for co-robot which is a heart of industry 4.0 factory automation. Compared with modeling based research for recognizing motion of co-robot, there are few attempts to predict motion based on sensor data. Therefore, in this paper, an experimental environment for collecting current and inertia data in co-robot to detect the motion of the robot is built, and a motion prediction model based on the collected sensor data is proposed. The proposed method classifies the co-robot's motion commands into 9 types based on joint position and uses current and inertial sensor values to predict them by accumulated learning. The data used for accumulating learning is the sensor values that are collected when the co-robot operates with margin in input parameters of the motion commands. Through this, the model is constructed to predict not only the nine movements along the same path but also the movements along the similar path. As a result of learning using SVM, the accuracy, precision, and recall factors of the model were evaluated as 97% on average.

• Korean Journal of Remote Sensing
• /
• v.27 no.5
• /
• pp.507-520
• /
• 2011

Conventional radar altimeter system measured directly the distance between the satellite and the ocean surface and frequently used by aircraft for approach and landing. The radar altimeter is good at flat surface like sea whereas it is difficult to determine precise three dimensional ground coordinates because the ground surface, unlike ocean, is very indented. To overcome this drawback of the radar altimeter, we have developed and validated the interferometric radar altimeter signal processing which is combined with new synthetic aperture and interferometric signal processing algorithm to extract precise three-dimensional ground coordinates. The proposed algorithm can accurately measure the three dimensional ground coordinates using three antennas. In a set of 70 simulations, the averages of errors in x, y and z directions were approximately -0.40 m, -0.02 m and 4.22 m, respectively and the RMSEs were about 3.40 m, 0.30 m and 6.20 m, respectively. The overall results represent that the proposed algorithm is effective for accurate three dimensional ground positioning.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.4
• /
• pp.167-178
• /
• 2014

As large-scale housing sites are being developed rapidly in Sejong City, which was launched in 2012 for resolving the adverse effects of overconcentration in the capital area, promoting balanced development of the country, and reinforcing national competitiveness, changes in spatial structure are expected in the surrounding areas. For setting the directions of urban planning, it is essential to understand changes in spatial structure. This study purposed to measure changes in the spatial structure of neighboring areas resulting from the construction of Sejong City by approaching from the aspect of spatial interaction. In the analysis, we calculated population potential for future spatial interaction using the accessibility model, and interpreted quantitatively and qualitatively the outcomes of spatial interaction among neighboring areas before and after the construction of Sejong City using population potential as an indicator. According to the results of the analysis, the impact range of the population potential of the subject areas had been shrinking continuously since 1995, and in 2013 population potential dispersed as the population concentrated on and around Cheonan City. Although Sejong City, as a new area of population potential, was not found to play the role of a pivotal point for the surrounding areas, it is probably because the analysis was made just after people began to move to Sejong City. Accordingly, along with the effort of Sejong City to reach the planned population, it is necessary to keep monitoring changes in related factors and changes in the spatial structure of the surrounding cities resulting from the growth of population.

• Geophysics and Geophysical Exploration
• /
• v.9 no.1
• /
• pp.10-18
• /
• 2006

We measured the changes in P-wave velocity that occur when injecting $CO_2$ in gaseous, liquid, and supercritical phases into water-saturated anisotropic sandstones. P-wave velocities were measured in two cylindrical samples of Tako Sandstone, drilled along directions normal and parallel to the bedding plane, using a piezo-electric transducer array system. The velocity changes caused by $CO_2$ injection are typically -6% on average, with maximum values about -16% for the case of supercritical $CO_2$ injection. P-wave velocity tomograms obtained by the differential arrival-time method clearly show that $CO_2$ migration behaviour is more complex when $CO_2$ flows normal to the bedding plane than when it flows parallel to bedding. We also found that the differences in P-wave velocity images were associated both with the $CO_2$ phases and with heterogeneity of pore distribution in the rocks. Seismic images showed that the highest velocity reduction occurred for supercritical $CO_2$ injection, compared with gaseous or liquid $CO_$ injection. This result may justify the use of the seismic method for $CO_2$ monitoring in geological sequestration.

• Journal of Radiation Protection and Research
• /
• v.31 no.4
• /
• pp.219-235
• /
• 2006

Based on the fact that studies on the use of radiations have not been largely conducted reflected on the importance of the use of radiations, the survey was performed to investigate the attitude on the use of radiations for some university students who have a high level of knowledges among average persons in order to extract certain directions for the education program to provide right information. The survey was performed for 517 university students from Oct. 10 to Oct. 15, 2005. The results of this survey can be summarized as follows. 1. Students who have experienced in the radiation related education presented statical differences in the results according to the majoring and monthly incomes. 2. Regarding the survey on the attitude of the use of radiations, the item of 'I agree to build a general hospital or university hospital where I lives in' was presented as the highest points of $3.73{\pm}1.004$, and the lowest point was recorded in the item of 'I agree to build an atomic wastes treatment facility where I live in' as the point of $2.63{\pm}1.091$. 3. The level of attitudes on 'I agree to build an atomic power plant or atomic wastes treatment facility where I live in' presented lower levels than that of the attitude on 'I agree to build an atomic power plant or atomic wastes treatment facility in my country'. 4. The lowest level recorded in the level of attitudes on 'I agree to build an atomic wastes treatment facility where I live in 'presented a significant difference according to the sex and grade.

• Journal of Radiation Protection and Research
• /
• v.44 no.4
• /
• pp.128-148
• /
• 2019

Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2-3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.