• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2019.11a
• /
• pp.77-78
• /
• 2019

Organic insulating materials can cause fatal toxic gases when burned, which can lead to human injury. As a combustible material, the risk of fire spreading is great. Therefore, there is a need for a study on the lightweight cured body for the non-combustible inorganic insulation to replace the flammable organic insulation. This study aims to examine the properties of lightweight foamed concrete according to the dilution concentration of animal foaming agent which forms a closed void when foaming as a part of the experiment to examine the utility of the lightweight foamed concrete as an insulating material. Bubbles occupy a large volume of lightweight foam concrete and have a great influence on the properties. Therefore, the stability of the bubble is very important, and as a result of the experiment, it is determined that 3% of the smallest vesicles are prepared at the proper dilution concentration.

• Earthquakes and Structures
• /
• v.26 no.2
• /
• pp.163-174
• /
• 2024

Dynamic equilibrium equations for finite element analysis were derived for the free field one-dimensional shear wave propagation through the horizontally layered soil deposits with the elastic half-space. We expressed Rayleigh's viscous damping consisting of mass and stiffness proportional terms. We considered two cases where damping matrices are defined in the total and relative displacement fields. Two forms of equilibrium equations are presented; one in terms of total motions and the other in terms of relative motions. To evaluate the performance of new equilibrium equations, we conducted two sets of site response analyses and directly compared them with the exact closed-form frequency domain solution. Results show that the base shear force as earthquake load represents the simpler form of equilibrium equation to be used for the finite element method. Conventional finite element procedure using base acceleration as earthquake load predicts exact solution reasonably well even in soil deposits with unrealistically high damping.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.29 no.12 s.148
• /
• pp.1582-1594
• /
• 2005

The purpose of this study is to rediscover the value of form in fashion design by developing a new perspective of design appreciation. By examining and modifying the theories of Wolfflin and Belong, this paper tries to of for a new perspective for analyzing the characteristics of form in fashion designers' works. The three new perspective, Flat & Rounded, Closed & Opened and Part & Whole, can be used to analyze the formative aesthetic character of Vionnet's and Dior's works. Ten of Vionnet's and eleven of Dior's representative works selected and applied Delong's visual priority diagram to analyze their character. Vionnet and Dior, emphasized form and construction in their design and applied geometric shapes in their works. The main differences between Vionnet and Dior is that Vionnet's work transforms from geometric shapes in 2-dimentional space to drapery shapes in 3-dimensional space, Dior's work displays geometric shapes in 3-dimensional space. Vionnet created new formative art through the relationship between the clothes and human body. Vionnet's work has distinctively different qualities depending on whether the space is 2-dimensional or 3-dimensional showing transposition of form. In 2-dimensional space, Vionnet's works consist of triangles, rectangles and circles which are 'flat' and 'closed' in quality. These transform to solid forms by draping bias fabrics, which have a 'rounded' and 'open' quality. Dior tended to show artificial form rather than the natural lines of the body which is very different with Vionnet. Dior created clothes by using solid geometric form such as spheres, prisms, cylinders, pyramids and cubes in 3-dimensional space, which were visualized through constructive technique such as dart manipulation, boning, gathering, tucking, pleating, shirring and layering. Dior's works have their own form which does not relate with body shape. So his Works have a 'rounded' and 'closed' quality.

• Survey Research
• /
• v.18 no.4
• /
• pp.127-147
• /
• 2017

Despite the importance of questionnaires, little survey methodology research on questionnaire design has been conducted in Korea. The purpose of this study was to explore whether two questionnaire forms (close-ended vs. open-ended questions) about 'the most important problem in Korea' elicited similar responses. During the 2016 Korean General Social Survey (KGSS), a random half of respondents were asked the open-ended question form and the remaining half were asked the close-ended question form. While the economy is the most mentioned response (35% vs. 33.2%) to both close-ended and open-ended question forms, there is similarity in the order of highly mentioned responses if we consider that 'politics' is not provided as one of response categories in the close-ended question form. The order of second to fourth response category is crime (24.4%), education (15.4%), and poverty (6.3%) to the closed-ended question form, and politics (10.8%), crime (9.5%), and education (7.6%) to the open-ended question form. Also, the characteristics of respondents who responded with the economy as being the most important are slightly different between the two halves in terms of age, household income, and satisfaction with economic condition. Our findings suggest that we need to be careful when we adopt questions developed in other countries and to consider using survey experiments in pre-testing questionnaire items.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.12 no.1
• /
• pp.85-95
• /
• 1992

The moment distribution method has been widely used for the past sixty years for determining the end moments of structural frames. However, the method trends to show more complexity of the procedures and approximation of the results as the degree of indeterminancy increases. The previous study proposed closed form formulas for the analysis of the continuous beams up to four spans. These formulars show simpler forms and provide perfectly rigorous solution in comparision with the moment distribution method. This study proposes closed form formulas for the analysis of multi-span continuous beams which are basically similar to the equations developed in the previous study. It is shown that these formulars may also produce more rigorous results and lead to simpler calculation processes. The proposed approach may be one of the new methods for the analysis of multi-span continuous beams or the rigid frames.

• Journal of Korean Physical Therapy Science
• /
• v.25 no.1
• /
• pp.1-10
• /
• 2018

Background: The purpose of this study was to ascertain the effects of core program exercise on balance in patients with chronic low back pain. Thirty-four subjects participated in this study, these subjects were assigned into two groups, a control group(n=17) and an experimental group(n=17). Methods: The subjects in the control group were received a conservative physical therapy and in the experimental group carried out the core program exercise for 30 minutes per day, three times a week during 6 weeks. In order to evaluate the progresses of balance ability, corresponding variables were measured at two times, pre and 6th week. The balance ability was assessed using GOOD BALANCE system. The collected data were analyzed by using the paired t-test and ANCOVA. In all statistical analyses, significance level, ${\alpha}$ was set by 0.05. Results: The results of this study were as follows: 1) In the position of left standing eye closed, there were significant difference of Y in the control group and X, Y, V in the experimental group. 2) In the position of right standing eye closed, there were significant difference of Y in the control group and X, Y, V in the experimental group. 3) In the position of dynamic balance 1, there were significant difference APV in experimental groups. 4) In the position of dynamic balance 2, there were significant difference MLV in experimental groups. 5) There were significances between the two group of X, V in static balance and APV in dynamic balance. Conclusion: The above results indicated that a core program exercise improved balance abilities in patients with chronic low back. The further studies should be focused at development of various modified forms of the core program exercise in keeping up the improvement effect of this exercise.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.32 no.5
• /
• pp.808-820
• /
• 2008

The costume of Islam cultural area has been affected by the strict social structure, formed by religion, and traditional costume of Islam has been maintained up to these days under the influence of religion. Islam Traditional Costume, which is the succession of the traditional costume of southwest Asia region, became armed with the form of closed costume due to the chastity and oppression. There are figurative features of Islam Folk Costume; first, the dimensional form due to the ampleness, covering the body, second, the reinforcement of closed form such as chador and burqa, third, the symbolism such as the adornment or incantational ornament, which has been inherited from the former times of Islam era, fourth, the color, simplified with black and white. The aesthetic values of Islam folk costume are represented with 'The beauty of abstinency', suppressing the ornamentation and color, caused by the strict social atmosphere under the influence of the form of traditional costume and religion, 'The beauty of concealment' due to the closeness, with affluent costume forms, covering the body and even concealing the face, and 'The beauty of symbol' which is demonstrated with incantational ornamentation of face and interior decoration. In some nations amongst Islam nations, the wearing of hijab is strictly regulated but black chador and burqa are regarded as negative symbols, representing the closeness and oppression of Islam. It is the product of Orientalism from the western perspective. The Islam Hijab culture is the symbol of oppression towards women, but, on the other hand, it is the device to protect women and the traditional culture, symbolizing the identity.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.38 no.4
• /
• pp.1-10
• /
• 2001

The 3-step cell search has been considered for fast acquisition of the scrambling code unique to a cell in the W -CDMA system. In this paper, the performance of the cell search scheme is analyzed in Rayleigh fading channels. And the system parameters for cell search scheme and the design parameters for the receivers are examined. The probabilities of detection, miss and false alarm for each step are derived in closed forms based on the statistics of CDMA noncoherent demodulator output. Through the analysis, the effect of threshold setting and post detection integration for each step is investigated, and the optimal values of the power allocation for the synchronization channels are also considered. The number of post-detection integrations for each step is a design parameter for the receiver, and the optimum values may depend on not only the power allocation for each channel related to the cell search, but the false alarm penalty time. It is shown that optimal values could be determined through the analysis. Also, the cumulative probability distribution of the average cell search time is obtained.

• Journal of the Korean housing association
• /
• v.13 no.5
• /
• pp.31-42
• /
• 2002

This comparative study between Korean and German housings aims at understanding different structural systems in the indoor and outdoor spaces, depending upon the user′s perception of the socio-cultural attributes. The analysis starts with four alternative contrary assumptions, that appear in morphological forms of dwelling; 1) linear distribution vs. areal distribution of residential districts, 2) mirror system vs. comb system in the layout of plot plans 3) organization of front vs. back outdoor spaces and 4) opening vs. closing in the indoor spaces. A clear difference is found between Korean and German samples in view of public and private relationships between indoor and outdoor spaces as well as the intermediate space. In the korean housing there always exists a symbolic and psychological territory of a certain sphere. On the other hand, outdoor space passes through various phases only to form a certain hierarchy even in a private space and, thereby, sets a boundary between private and public areas. In the case of Germany, the building itself draws a clear line between private and public outdoor spaces, and therefore the outdoor space has a "front" and "back". Thus, Germany′s private space may face a genuine public space and street, which is rare in the Korean housing. Although the layout of indoor space in the korean housing tends to be open, such an openness may be outstanding in living and dining spaces, kitchen and various accesses to rooms. In the case of Germany, such indoor spaces are usually closed to each other. Thus corridors act to separate these spaces. Such differences are analysed to be due to the different perceptions of interpersonal and socio-cultural attributes as intra-family and inter-neighbor relationships or communications.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.11 no.4
• /
• pp.45-54
• /
• 1991

The closed forms of mass matrix with rotational inertia matrix are developed for free vibration analysis in space structures containing linearing tapered members with cross section of thin-walled tube. The exact displacement functions are used for formulating mass matrix. The very small slopes of the tapered member are used in usual practice, such that the series expansion forms of these are also developed to avoid numerical failure in vibration analysis. Significant improvements of accuracy and efficiency of free vibration analysis are achieved by using the mass matrices developed in this study. Frequencies of free vibration of tapered members are compared with solutions based upon stepped representation of beam element.