• Magazine of the Korea Concrete Institute
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• v.6 no.1
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• pp.120-130
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• 1994

The purpose of this study is to propose the analytical model for the hysteretic behavior of Reinforced Concrete bearn-column joints under various loading history. Discrete line elernents , YVith inelastic rotational spring was adopted to consider the movement of plastic hinging zone influenced by the details of longitudinal reinforcements. Also hysteretic model was constructed by excluding such variables which can not be utilized in dynamic analysis of Reinforced Concrete. structure that it will be adoptable in two-dimensional inelastic frame ardysis with 6-DOF. From the analysis of previous test results, it was found that stiffness deterioration caused by inelastic hysteretic loadings can be predicted by the functron of basic pinching coefficients, ductility ratio.and yield strength ratio of members. Strength degradation coefficients were newly proposed to explain the difference of inelastic behavior of members caused by spacing ratio of transverse steel and sectlon aspect ratio. The energy dissipation capacities calculated using the analytical model proposed in thls paper show a good agreements w~lh test results by an error of 10~20%.

• Journal of Korean Elementary Science Education
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• v.36 no.4
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• pp.379-393
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• 2017

This study analyzed the relationship between self-directedness of science-gifted elementary students and their expression of scientific creativity in science-gifted class. A science-gifted program on the topic of Hydraulic Machine was implemented to 34 fifth-graders in the Science-Gifted Education Center of an education office in Seoul, Korea for four weeks. The self-directedness of the gifted students was divided into three types of 'General, Scientific, and Topic-Related Self-Directedness'. The products of the students' activities were assessed by using a scientific creativity assessment formula. Qualitative research, such as analysis of observations and interviews, was also conducted in order to identify characteristics that were not apparently revealed by quantitative data. The main results of this study are as follows: First, science-gifted elementary students' general self-directedness and their scientific creativity were significantly correlated (r=.373). Second, the students' scientific self-directedness and scientific creativity did not have a significant correlation (r=.294). Third, there was a positive correlation between the students' topic-related self-directedness and their expression of scientific creativity. Their self-rated scores (r=.420) for the topic-related self-directedness and the number of activity types associated with the topic had a positive correlation (r=.350). Fourth, the students were categorized into four groups according to the levels of their self-directedness and scientific creativity, and the result showed that Type HH (high self-directedness and high scientific creativity) was the most common type (15 students, 38.5%), followed by Type LL (low self-directedness and low scientific creativity) (11 students, 28.2%). Eight (20.5%) and five students (12.8 %) belonged to Type LH (low self-directedness and high scientific creativity) and Type HL (high self-directedness and low scientific creativity) respectively. Fifth, the classroom observation of the students in groups revealed that groups with more number of Type HH demonstrated better cooperation and performance. Sixth, the analysis results of the observation were almost matched to the results of the self-directedness and scientific creativity tests. The students with higher self-directedness demonstrated active class participation and good cooperative skills. The students with higher scientific creativity had a tendency to generate creative ideas more frequently in given situations. Seventh, dynamic activities were perceived as enjoyable and exciting by 76.9% of the students, but static activities that require creativity were regarded as interesting only by 23.1% of the students. Among the students who were satisfied with both the creative and static activities, Type HH accounted for the largest proportion (55.6%). In conclusion, factors such as students' interests, initiatives, and attitudes displayed through voluntary participations originated from their own daily life can predict the degree of scientific creativity associated with the topic. Also, when students were categorized into four types according to the level of self-directedness and scientific creativity, there was a tendency of active behavior in class, cooperative skill, and activity satisfaction. This suggested that we should consider self-directedness and scientific creativity in selecting the gifted, grouping them in class, and designing and executing programs for science-gifted elementary students.

• Journal of the Korean Society of Costume
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• v.59 no.3
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• pp.109-130
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• 2009

This study examines the rotor characteristics of Guybang culture (women's living in Joseon) relics which the life images and mental world of women in Joseon if expressed to prepare rotor data to be utilized in modern design and information for color identity establishment of Korean women culture. The result of this study is as following: 1. From 176 pieces of relic photos, total of 1380 color chips were extracted. For color analysis, 1368 units (99.1%) of color data excluding achromatic 12 units (0.9%) among 1380 units of colors were used. With the standard of 10 color wheel of Munsell Color System, the result of studying distributions according to frequency, red was the highest by 25.9%, yellow was 21.4% in women's goods in Joseon period which the ratio of red and yellow was 473%. Other than that, GY 14.6%, YR 11.3% and RP 11.1% followed next which is studied that the warm colors that conveys enjoyable and glamorous feelings composed 84.3%; 2. As a result of tone analysis, high value low chroma ltg color showed highest distribution of 20% and d was 12.2%, b was 11.7% and sf was 8.8%. Generally, it showed high frequency in high value cocors such as ltg, sf and b of 40.5%t and in low chroma (ltg) and medium chroma (d, sf) of 41% and colors in bright and calm image was used the most. 3. As a result of analyzing relationship between hue & tone, the ltg tone of Y close to white in traditional color sensibility showed the highest frequency of 9.6% and ltg tone of GY(6.4%), b tone of RP(6.1%), and v(5.4%), b(5.4%), dp(5.3%) of R followed next. 4. As a result of analyzing the characteristics of coloring, it showed that in case of coloring contrasting hues, it is adjusted similar tones and in case of coloring less contrasting hue, the difference in tone is adjusted to be rather large to make harmonized coloring. Moreover, in case of coloring similar hues, the ratio of using same tone and similar tone was large which the coloring of calm image and dynamic image is all used.

• Journal of Korea Technology Innovation Society
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• v.13 no.1
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• pp.140-159
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• 2010

The main purpose of this study is to improve the understanding of the failures of venture companies. The study attempts to analyze the causes and the processes of venture failures and the different paths that led to such failures. For the research, 116 firms registered with the Korea Venture Business Association in 1997 were surveyed and traced in 2000. A questionnaire was sent to 105 companies that were operating at the time and 76 of them returned responses. In 2008, the 76 companies were re-traced, and it was found that 41 of them had failed while 35 survived. Through this process, a set of longitudinal data was gathered about the changes in strategies, environments, and organizational structures. Accordingly, t-test and ANOVA analysis were performed on the different causes and processes of venture failures, as well as the taxonomy according to the changes in circumstances. Empirical findings can be summarized as follows. Venture companies failed due to various reasons and there were very different failing processes. In addition, this study found that various failing paths existed among failed venture companies and different factors affected company failures. Considering these findings, this research is clearly advanced and can be distinguished from other existing researches in terms of the dynamic understanding of the failures of venture companies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.303-311
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• 2020

The acreage of tangerines in the U.S. sharply rose from 19,000 ha in 2009 to 27,000 ha in 2016, an increase of 42% in 7 years. Considering the recent surge in tangerine exports to Japan, the export volume of 6-7 thousand tons is highly likely to increase in the future. Therefore, the purpose of this study was to analyze the economic impact of U.S. tangerine imports on the Korean citrus industry under various scenarios. In order to examine the possibility of imports of U.S. tangerines, the unit price of U.S. exports to Japan was used since U.S. tangerines are not imported to South Korea. Citrus fruits are divided into field citrus, house citrus, and late-maturing citrus (including winter season citrus) based on the cultivation method and variety used to analyze. Considering both the field and house seasons, the import volume of U.S. tangerines can be expected to rise from roughly 4,700 tons in 2021 to 10,000 tons in 2027. Imports of U.S. tangerines may be pushed up or delayed depending not only on the harvest method and quality of domestic field and house citrus but also on the harvest of U.S. tangerines. However, it is necessary to note that tangerines could be imported after 2021, when the tariff rate on U.S. tangerines will fall below 50%.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.794-806
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• 2020

This study was conducted in order to attain an in-depth understanding of and describe the Ego-Integrity Phenomenon of the elderly of age 65 and older. The data was collected from June 2020 to July 2020 as an in-depth interview consisting of semi-structured questions. The data was analyzed using the Colaizzi's method, one of the phenomenology methods. All interviews were recorded and transcribed for analysis. Through analysis, 309 significant statements were extracted, and 88 formulations of meaning, 53 themes, 16 theme clusters, and 5 categories were derived. The categories and the theme clusters are as such : 'reflecting on the past life with delight' ('fruitfulness over the lifetime', 'achieving through fulfilling responsibilities', 'achieved specially and gratefully'), 'Currently lonely and distressed due to the bitter old days' ('Physical health needs and psychosocial needs are not met', 'Wasn't able to make good choices for parents and children', 'Elderly life is not easy'), 'Satisfaction from enduring tough and difficult journeys in life' ('Compensated for hard work at workplace and home', 'Problem solved through endurance and overcoming', 'Living a healthy elderly life by escaping from the habits of the past'), 'Realizing the way of life as an elderly' ('Now is the best and most satisfying moment', 'Managing self in old age', 'Living passionately, though it may be late', 'Retiring from the forefront of life with an abundant heart'), 'Passing on beautifully' ('Desires toward the later years', 'Hope during the last moments', 'Appearance and emotions when death approaches'). It was observed that during the Ego-Integrity Phenomenon of the elderly, they have come to discern the meaning of life by reminiscing the regrets and difficulties of the past, and through this reminiscence, they have come to attain a positive and transcendental hope for the rest of their lives. The Ego-Integrity of the elderly appeared to be subjective, dynamic, and occurring simultaneously rather than continuously. It is recommended to develop a variety of nursing interventions while taking into consideration the age and the type of experience of the elderly.

• Journal of Biomedical Engineering Research
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• v.38 no.1
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• pp.9-15
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• 2017

Recently, flexible cages have been introduced in an attempt to absorb and reduce the abnormal load transfer along the anterior parts of the spine. They are designed to be used with the pedicle screw systems to allow some mobility at the index level while containing ROM at the adjacent level. In this study, a finite element (FE) study was performed to assess biomechanical efficacies of the flexible cage when combined with pedicle screws with flexible rods. The post-operated models were constructed by modifying the L4-5 of a previously-validated 3-D FE model of the intact lumbar spine (L2-S1): (1) Type 1, flexible cage only; (2) Type 2, pedicle screws with flexible rods; (3) Type 3, interbody fusion cage plus pedicle screws with rigid rods; (4) Type 4, interbody fusion cage plus Type 2; (5) Type 5, Type 1 plus Type 2. Flexion/extension of 10 Nm with a compressive follower load of 400N was applied. As compared to the Type 3 (62~65%) and Type 4 (59~62%), Type 5 (53~55%) was able to limit the motion at the operated level effectively, despite moderate reduction at the adjacent level. It was also able to shift the load back to the anterior portions of the spine thus relieving excessively high posterior load transfer and to reduce stress on the endplate by absorbing the load with its flexible shape design features. The likelihood of component failure of flexble cage remained less than 30% regardless of loading conditions when combined with pedicle screws with flexible rods. Our study demonstrated that flexible cages when combined with posterior dynamic system may help reduce subsidence of cage and degeneration process at the adjacent levels while effectively providing stability at the operated level.

• The Journal of the Korea Contents Association
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• v.18 no.9
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• pp.34-43
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• 2018

The purpose of this study is to develop measurement program model for a human being-oriented product through the between the evaluation factors of portrait and general preferences of portraits. We added new items that are essential to the image evaluation by analysing previous studies. In this study, We identified the facial focus for the first step, and the portraits were evaluated by dividing it into objective and subjective image quality evaluation items. RSC Contrast and Dynamic Range were selected as the Objective evaluation items, and the numerical values of each image could be evaluation items, and the numerical values of each image could be evaluated by statistical analysis method. Facial Exposure, Composition, Position, Ratio, Out of focus, and Emotions and Color tone of image were selected as the Subjective evaluation items. In addition, a new face recognition algorithm is applied to judge the emotions, the manufacturer can get the information that they can analyze the people's emotion. The program developed to quantitatively and qualitatively compiles the evaluation items when evaluating portraits. The program that I developed through this study can be used an analysis program that produce the data for developing the evaluation model of the product more suitable to general users of imaging systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.458-465
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• 2020

The purpose of this study is to analyze the effect of policy in Jeju, using a macro-economic forecasting model of Jeju. First, the model's reality explanatory power improved by updating its statistics to 2017 and expanding new policy variables and modules. Also, the industrial structure of the model was further subdivided and extended to be considered simultaneously in the demand side of Keynesian theory. Second, it was determined that the predictive power for the model of this study was better than that of the existing model. However, with some endogenous variables, it was possible to identify implications that should be developed and considered when the model is improved with additional data in the future. Third, when the second airport construction was considered, it was observed that its effect was an increase of 1.25 times for GRDP, 1.2 times for employment, 1.48 times for private consumption, and 2.06 times for investment. Also, the economic growth rate was estimated to be 1.6% point higher than when the second airport was not constructed. Finally, the results of this study are expected to be used for policy decision making of the Jeju Government.

• Computers and Concrete
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• v.22 no.3
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• pp.337-353
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• 2018

The present study focuses on examining the structural behaviour of steel-fibre-reinforced concrete (SFRC) beams under high rates of loading largely associated with impact problems. Fibres are added to the concrete mix to enhance ductility and energy absorption, which is important for impact-resistant design. A simple, yet practical non-linear finite-element analysis (NLFEA) model was used in the present study. Experimental static and impact tests were also carried out on beams spanning 1.3 meter with weights dropped from heights of 1.5 m and 2.5 m, respectively. The numerical model realistically describes the fully-brittle tensile behaviour of plain concrete as well as the contribution of steel fibres to the post-cracking response (the latter was allowed for by conveniently adjusting the constitutive relations for plain concrete, mainly in uniaxial tension). Suitable material relations (describing compression, tension and shear) were selected for SFRC and incorporated into ABAQUS software Brittle Cracking concrete model. A more complex model (i.e., the Damaged Plasticity concrete model in ABAQUS) was also considered and it was found that the seemingly simple (but fundamental) Brittle Cracking model yielded reliable results. Published data obtained from drop-weight experimental tests on RC and SFRC beams indicates that there is an increase in the maximum load recorded (compared to the corresponding static one) and a reduction in the portion of the beam span reacting to the impact load. However, there is considerable scatter and the specimens were often tested to complete destruction and thus yielding post-failure characteristics of little design value and making it difficult to pinpoint the actual load-carrying capacity and identify the associated true ultimate limit state (ULS). To address this, dynamic NLFEA was employed and the impact load applied was reduced gradually and applied in pulses to pinpoint the actual failure point. Different case studies were considered covering impact loading responses at both the material and structural levels as well as comparisons between RC and SFRC specimens. Steel fibres were found to increase the load-carrying capacity and deformability by offering better control over the cracking process concrete undergoes and allowing the impact energy to be absorbed more effectively compared to conventional RC members. This is useful for impact-resistant design of SFRC beams.